Answer:
4i.
Step-by-step explanation:
To find the flux through the square, we use the divergence theorem for the flux. So Flux of F(x,y) = ∫∫divF(x,y).dA
F(x,y) = hxy,x - yi
div(F(x,y)) = dF(x,y)/dx + dF(x,y)dy = dhxy/dx + d(x - yi)/dy = hy - i
So, ∫∫divF(x,y).dA = ∫∫(hy - i).dA
= ∫∫(hy - i).dxdy
= ∫∫hydxdy - ∫∫idxdy
Since we are integrating along the boundary of the square given by −1 ≤ x ≤ 1, −1 ≤ y ≤ 1, then
∫∫divF(x,y).dA = ∫₋₁¹∫₋₁¹hydxdy - ∫₋₁¹∫₋₁¹idxdy
= h∫₋₁¹{y²/2}¹₋₁dx - i∫₋₁¹[y]₋₁¹dx
= h∫₋₁¹{1²/2 - (-1)/2²}dx - i∫₋₁¹[1 - (-1)]dx
= h∫₋₁¹{1/2 - 1)/2}dx - i∫₋₁¹[1 + 1)]dx
= 0 - i∫₋₁¹2dx
= - 2i[x]₋₁¹
= 2i[1 - (-1)]
= 2i[1 + 1]
= 2i(2)
= 4i
A research worker gave a scholastic aptitude test to a sample of eighth graders. Then he correlated the aptitude test scores with the chronological ages of the subjects. He found a correlation of - .42. How should this result be interpreted?
Answer: There is an moderate relationship between the aptitude test scores with the chronological ages of the subjects.
Step-by-step explanation:
The correlation coefficient tells about the strength and direction of the relation ship between any 2 variables. When the value of correlation coefficient lies between -0.5 to -0.3 or 0.3 to 0.5, then it indicates that there is moderate association between variables.Here , variables → aptitude test scores and chronological ages of the subjects.
Since correlation coefficient (-0.42) lies between -0.5 and -0.3 .
[-0.5< -0.42< -0.3]
That means there is an moderate relationship between the aptitude test scores with the chronological ages of the subjects.
What is the distance between the coordinates (4,2) and (0,2)
Answer: Hi!
The distance between the coordinates (4,2) and (0,2) is 4 units.
The coordinates have the same location on the y axis, but the coordinates have different locations on the x axis. (4,2) is 4 units to the right of the x axis and 2 up on the y axis, while (0,2) goes just straight up to 2 on the y axis. If we graphed these, the two points would be aligned with each other, but a distance of 4 units would separate them horizontally.
Hope this helps!
The dot plot represents a sampling of ACT scores: dot plot titled ACT Scores with Score on the x axis and Number of Students on the y axis with 1 dot over 24, 3 dots over 26, 3 dots over 27, 5 dots over 28, 3 dots over 30, 3 dots over 32, 1 dot over 35 Which box plot represents the dot plot data? box plot titled ACT Score with a minimum of 24, quartile 1 of 25, median of 26, quartile 3 of 29, and maximum of 35 box plot titled ACT Score with a minimum of 23, quartile 1 of 25, median of 26, quartile 3 of 29, and maximum of 36 box plot titled ACT Score with a minimum of 23, quartile 1 of 27, median of 30, quartile 3 of 34, and maximum of 36 box plot titled ACT Score with a minimum of 24, quartile 1 of 27, median of 28, quartile 3 of 30, and maximum of 35
Answer:
box plot titled ACT Score with a minimum of 24, quartile 1 of 27, median of 28, quartile 3 of 30, and maximum of 35
Step-by-step explanation:
The scores of the students represented on the dot plot are:
1 dot => 24
3 dots => 26, 26, 26
3 dots => 27, 27, 27
5 dots => 28, 28, 28, 28, 28
3 dots => 30, 30, 30
3 dots => 32, 32, 32
1 dot => 35
Quickly, we can ascertain 3 values from these data points of which we can use to find out which box plot represents the dot plot data.
The minimum score = 24
The maximum score = 35
The median score is the 10th value, which is the middle value of the data point = 28
Therefore, we can conclude that: "box plot titled ACT Score with a minimum of 24, quartile 1 of 27, median of 28, quartile 3 of 30, and maximum of 35".
Solve for x: x/25 > 5
Answer:
x>125
Step-by-step explanation:
Answer:
x > 125
Step-by-step explanation:
Multiply each side by 25, so it now looks like this: x > 125I hope this helps!
What is the distance between y=2x+4 and y=2x-1?
Answer:
Y=2(1)+4
Y=2+4
Y=6
Step-by-step explanation:
Please follow me
Please help!! find the value of the expression
Answer:
7
Step-by-step explanation:
First plug in the variable amounts so the expression now looks like this:
(3 × 4 - 12) + 1/2(4 × 6 - 10)
Now, start by solving the multiplication parts first, so it now looks like this:
(12 - 12) + 1/2(24 - 10)
Now, apply the rules of order of operation, so start by solving what's in parenthesis. It should now look like this: (0) + 1/2(14)
Next, solve the multiplication part, so it now looks like this: 0 + 7
Solve that and the answer is 7.
Which is a factor of: 2x2+10x+8 ?
Answer:
2 ( x+4) ( x+1)
Step-by-step explanation:
2x^2+10x+8
Factor out 2
2 ( x^2 +5x+4)
What two numbers multiply to 4 and add to 5
4*1 = 4
4+1 = 5
2 ( x+4) ( x+1)
[tex] \large{ \underline{ \underline{ \bf{ \pink{To \: factorise}}}}}[/tex]
2x² + 10x + 8Factorisation:By middle term factorisation,
⇛ 2x² + 2x + 8x + 8
⇛ 2x(x + 1) + 8(x + 1)
⇛ (2x + 8)(x + 1)
⇛ 2(x + 4)(x + 1)
☃️ Now you can break it down and check which are the factors of the polynomial according to options.
━━━━━━━━━━━━━━━━━━━━
3. A jogger runs 4 miles on Monday, 5 miles on
Tuesday, 3 miles on Wednesday, and 5 miles on
Thursday. He doesn't run on Friday. How many
miles did he run in all?
Answer:
17 miles
Step-by-step explanation:
4+5+5+3=17
Of 900 people surveyed, 480 were male and 410 had cell phones. Of those with cell phones, 290 were female. What is the probability that a person surveyed was either male or had a cell phone? A. 600/900 = 0.6667 B. 770/900 = 0.8556 C. 360/900 = 0.40 D. 820/900 = 0.9111
Answer:
C. 360/900 = 0.40
Step-by-step explanation:
The number of the males that are using cellphone and the females who are using cell phones are in total 410. The total people surveyed are 900 people. There are total 480 males and rest 420 are females. Among the 420 females there are 290 females who use cellphones. The probability for males can be given by 360/900.
A boutique wants to make at least $127 profit from purses this week. The boutique earns $7 profit from each purse. How many purses must be sold?
Answer:
19 purses
Step-by-step explanation:
Set up an inequality where x represents the number of purses:
127 [tex]\geq[/tex] 7x
Solve for x by dividing each side by 7:
18.14 [tex]\geq[/tex] x
Round up to 19 because purses have to be whole
So, 19 purses have to be sold.
Hector's school is holding a fitness challenge. Student are encouraged to exercise at least 2 1/2 hours per week. Hector exercises about the same number of hours each week. During a 4-week period, he exercises for 11 1/2 hours. Hector wants to compare his exercise rate with the fitness challenge rate. How many hours per week does Hector exercise?
Hector outperformed the challenge rate as he exercised 2.88 hours a week.
It is best to convert the mixed fraction to decimals for easier calculation.
The students are encouraged to exercise 2¹/₂ hours per week. In decimals this is:
= 2 + ¹/₂
= 2 + 0.5
= 2.5 hours per week
In the 4 week period, Hector exercised 11¹/₂ hours which is:
= 11 + ¹/₂
= 11 + 0.5
= 11.5 hours
The number of hours he exercised per week is:
= Number of hours in total / Number of weeks
= 11.5 / 4
= 2.88 hours per week
When compared to the fitness challenge rate, we can conclude that Hector outperformed the challenge rate
Find out more at https://brainly.com/question/17951676.
Answer:
The answer is 2 7/8
Smoking by Race for Males Aged 18-24
Smoker Nonsmoker Row Total
(S) (N)
White(W) 290 560 850
Black(B) 30 120 150
Column Total 320 680 1,000
Calculate the probabilities given below (Round your answers to 4 decimal places.):
i. P(S) 0.3200
ii. P(W) 0.8500
iii. P(S | W) 0.2720
iv. P(S | B) 0.0300
v. P(S and W) 0.9062
vi. P(N and B) 0.1765
Answer:
(i) 0.32 (ii) 0.85
(iii) 0.3412 (iv) 0.20
(v) 0.29 (vi) 0.12
Step-by-step explanation:
The data provided is as follows:
Race Smoker (S) Nonsmoker (N) Row Total
White(W) 290 560 850
Black(B) 30 120 150
Column Total 320 680 1,000
(i)
Compute the value of P (S) as follows:
[tex]P(S)=\frac{n(S)}{N}=\frac{320}{1000}=0.32[/tex]
P (S) = 0.32.
(ii)
Compute the value of P (W) as follows:
[tex]P(W)=\frac{n(W)}{T}=\frac{850}{1000}=0.85[/tex]
P (W) = 0.85.
(iii)
Compute the value of P (S|W) as follows:
[tex]P(S|W)=\frac{n(S\cap W)}{n(W)}=\frac{290}{850}=0.3412[/tex]
P (S|W) = 0.3412.
(iv)
Compute the value of P (S|B) as follows:
[tex]P(S|B)=\frac{n(S\cap B)}{n(B)}=\frac{30}{150}=0.20[/tex]
P (S|W) = 0.20.
(v)
Compute the value of P (S∩W) as follows:
[tex]P(S\cap W)=\frac{n(S\cap W)}{T}=\frac{290}{1000}=0.29[/tex]
P (S∩W) = 0.29.
(vi)
Compute the value of P (N∩B) as follows:
[tex]P(N\cap B)=\frac{n(N\cap B)}{T}=\frac{120}{1000}=0.12[/tex]
P (S∩W) = 0.12.
A study was conducted by a research center. It reported that most shoppers have a specific spending limit in place while shopping online. The reports indicate that men spend an average of $240 online before they decide to visit a store. If the spending limit is normally distributed and the standard deviation is $20.
A. Find the probability that a male spent less than $210 online before deciding to visit a store.
B. Find the probability that a male spent between $270 and $300 online before deciding to visit a store.
C. Ninety percent of the amounts spent online by a male before deciding to visit a store are less than what value?
Answer:
(A) The probability that a male spent less than $210 online before deciding to visit a store is 0.0668.
(B) The probability that a male spent between $270 and $300 online before deciding to visit a store is 0.0655.
(C) Ninety percent of the amounts spent online by a male before deciding to visit a store is less than $265.632.
Step-by-step explanation:
We are given that the reports indicate that men spend an average of $240 online before they decide to visit a store. If the spending limit is normally distributed and the standard deviation is $20.
Let X = the spending limit
The z-score probability distribution for the normal distribution is given by;
Z = [tex]\frac{X-\mu}{\sigma}[/tex] ~ N(0,1)
where, [tex]\mu[/tex] = mean spending limit = $240
[tex]\sigma[/tex] = standard deviation = $20
So, X ~ Normal([tex]\mu=\$240,\sigma^{2} =\$20^{2}[/tex])
(A) The probability that a male spent less than $210 online before deciding to visit a store is given by = P(X < $210)
P(X < $210) = P( [tex]\frac{X-\mu}{\sigma}[/tex] < [tex]\frac{\$210-\$240}{\$20}[/tex] ) = P(Z < -1.50) = 1 - P(Z [tex]\leq[/tex] 1.50)
= 1 - 0.9332 = 0.0668
The above probability is calculated by looking at the value of x = 1.50 in the z table which has an area of 0.9332.
(B) The probability that a male spent between $270 and $300 online before deciding to visit a store is given by = P($270 < X < $300)
P($270 < X < $300) = P(X < $300) - P(X [tex]\leq[/tex] $270)
P(X < $300) = P( [tex]\frac{X-\mu}{\sigma}[/tex] < [tex]\frac{\$300-\$240}{\$20}[/tex] ) = P(Z < 3) = 0.9987
P(X [tex]\leq[/tex] $270) = P( [tex]\frac{X-\mu}{\sigma}[/tex] [tex]\leq[/tex] [tex]\frac{\$270-\$240}{\$20}[/tex] ) = P(Z [tex]\leq[/tex] 1.50) = 0.9332
The above probability is calculated by looking at the value of x = 3 and x = 1.50 in the z table which has an area of 0.9987 and 0.9332 respectively.
Therefore, P($270 < X < $300) = 0.9987 - 0.9332 = 0.0655.
(C) Now, we have to find ninety percent of the amounts spent online by a male before deciding to visit a store is less than what value, that is;
P(X < x) = 0.90 {where x is the required value}
P( [tex]\frac{X-\mu}{\sigma}[/tex] < [tex]\frac{x-\$240}{\$20}[/tex] ) = 0.90
P(Z < [tex]\frac{x-\$240}{\$20}[/tex] ) = 0.90
In the z table, the critical value of z that represents the bottom 90% of the area is given as 1.2816, i.e;
[tex]\frac{x-\$240}{\$20}=1.2816[/tex]
[tex]x-240=1.2816\times 20[/tex]
[tex]x=240 + 25.632[/tex]
x = 265.632
Hence, Ninety percent of the amounts spent online by a male before deciding to visit a store is less than $265.632.
Find the measure of each angle in Triangle ABC
Answer:
m<A = 133 degrees
m<B = 17 degrees
m<C = 30 degrees
Step-by-step explanation:
In a triangle, all the angles add up to 180 degrees.
So, adding all the angles gets us,
39x + 24
This equals 180 degrees so,
39x + 24 = 180
Subtract 24 from both sides,
39x + 24 - 24 = 180 - 24
39x = 156
Divide both sides by 39
x = 4
Now we have x = 4, we use this to plug in each equation of the angles.
m<A = 40(4) - 27 = 160 - 27 = 133
m<B = 25 - 2(4) = 25 - 8 = 17
m<C = 26 + 4 = 30
the amount of gas in sarahs car is uniformly distributed between 1 and 16 gallons. Calculate the probability that the amount of gas is exactly 7 gallons
Answer:
The probability that the amount of gas in Sarah's car is exactly 7 gallons is 0.067.
Step-by-step explanation:
Let the random variable X represent the amount of gas in Sarah's car.
It is provided that [tex]X\sim Unif(1, 16)[/tex].
The amount of gas in a car is a continuous variable.
So, the random variable X follows a continuous uniform distribution.
Then the probability density function of X is:
[tex]f_{X}(x)=\frac{1}{b-a};\ a<X<b[/tex]
For a continuous probability distribution the probability at an exact point is 0.
So, to compute the probability that the amount of gas in Sarah's car is exactly 7 gallons use continuity correction on both sides:
P (X = 7) = P (7 - 0.5 < X < 7 + 0.5)
= P (6.5 < X < 7.5)
[tex]=\int\limits^{7.5}_{6.5} {\frac{1}{16-1}} \, dx \\\\=\frac{1}{15}\times |x|^{7.5}_{6.5}\\\\=\frac{1}{15}\times (7.5-6.5)\\\\=\frac{1}{15}\\\\=0.0666667\\\\\approx 0.067[/tex]
Thus, the probability that the amount of gas in Sarah's car is exactly 7 gallons is 0.067.
Find the surface area of the figure. ft
Answer:
486
Step-by-step explanation:
Hello!
To find the surface area of a cube we use the equation
[tex]S = 6a^{2}[/tex]
S is the surface area
a is the side length
Put what we know into the equation
[tex]S = 6*9^{2}[/tex]
Solve
S = 6 * 81
S = 486
Hope this Helps!
Answer:486[tex]ft^{2}[/tex]
Step-by-step explanation:
surface area= 6[tex]l^{2}[/tex]
l=9
sa=6 ([tex]9^{2}[/tex])= 6 x 81=486[tex]ft^{2}[/tex]
PLZ HLEP QUICK!!! Which of the following is an arithmetic sequence? -2, 4, -6, 8, ... -8, -6, -4, -2, ... 2, 4, 8, 16, ...
Answer:
-8, -6, -4, -2, ...
Step-by-step explanation:
-8, -6, -4, -2, ... is an arithmetic sequence: each new term is obtained by adding 2 to the previous term.
Answer:
-8, -6, -4, -2
Step-by-step explanation:
"An arithmetic sequence is a list of numbers with a definite pattern. If you take any number in the sequence then subtract it by the previous one, and the result is always the same or constant then it is an arithmetic sequence."
I need help please help me
Answer: 72576m7
Step-by-step explanation:
2m x 8m x 6m x 9m x 7m x 6m x 2m
All together equals my answer 72576m7
Hope this helps!
Evaluate 26 + a if a = 8
Answer:
34
Step-by-step explanation:
= 26 + 8
= 34
What is x? Round to the nearest tenth
Answer:
x = 38.7
Step-by-step explanation:
Since this is a right triangle, we can use trig functions
tan theta = opp / adj
tan x = 8/10
taking the inverse tan of each side
x = tan ^-1 (8/10)
x=38.65980825
To the nearest tenth
x = 38.7
An article includes the accompanying data on compression strength (lb) for a sample of 12-oz aluminum cans filled with strawberry drink and another sample filled with cola.Beverage Sample Size Sample Mean Sample SDStrawberry Drink 10 537 22Cola 10 559 17Required:a. Does the data suggest that the extra carbonation of cola results in a higher average compression strength? Base your answer on a P-value.b. State the relevant hypotheses. c. Compute the test statistic value and find the P-value.d. State the conclusion in the problem context.e. What assumptions are necessary for your analysis?1. The distributions of compression strengths are approximately normal.2. The distributions of compression strengths have equal means. 3. The distributions of compression strengths are the same.4. The distributions of compression strengths have equal variances.
Answer:
Explained below.
Step-by-step explanation:
In this case we need to test whether the extra carbonation of cola results in a higher average compression strength.
(a)
The hypothesis for the test can be defined as follows:
H₀: The extra carbonation of cola does not results in a higher average compression strength, i.e. μ₁ - μ₂ = 0.
Hₐ: The extra carbonation of cola results in a higher average compression strength, i.e. μ₁ - μ₂ < 0.
(c)
Since the population standard deviations are not provided, we would use the t-test for difference between means.
The test statistic is:
[tex]t=\frac{\bar x_{1}-\bar x_{2}}{\sqrt{\frac{s_{1}^{2}}{n_{1}}+\frac{s_{2}^{2}}{n_{2}}}}[/tex]
[tex]=\frac{537-559}{\sqrt{\frac{22^{2}}{10}+\frac{17^{2}}{10}}}\\\\=\frac{-22}{8.792}\\\\=-2.502[/tex]
The test statistic value is -2.502.
(c)
Compute the p-value as follows:
[tex]p-value=P(t_{16}<-2.052)=0.012[/tex]
*Use a t-table.
The p-value of the test is 0.012.
(d)
The significance level of the test is, c
p-value = 0.012 < α = 0.05.
The null hypothesis will be rejected.
Conclusion:
The data suggest that the extra carbonation of cola results in a higher average compression strength.
(e)
The assumption necessary for the analysis is:
The distributions of compression strengths are approximately normal.
The correct option is (A).
What is (2/3 x 3/5) - (3/4 x 1/6)
Answer:
2/3×3/5=2/3. 3/4×1/6=1/8
2/3-1/8=11/40
Answer:
[tex] \boxed{ \frac{11}{40} }[/tex]Step-by-step explanation:
[tex]( \frac{2}{3} \times \frac{3}{5} ) - ( \frac{3}{4} \times \frac{1}{6} )[/tex]
Reduce the numbers with Greatest common factor 3
⇒[tex] \mathsf{(2 \times \frac{1}{5} ) - ( \frac{1}{4} \times \frac{1}{2} )}[/tex]
Calculate the product
⇒[tex] \mathsf{( \frac{2}{5} )- ( \frac{1}{4} \times \frac{1}{2}) }[/tex]
Subtract the fractions
⇒[tex] \mathsf{ \frac{2 \times 8 - 1 \times 5}{40} }[/tex]
⇒[tex] \mathsf{ \frac{16 - 5}{40} }[/tex]
⇒[tex] \mathsf{ \frac{11}{40} }[/tex]
Hope I helped!
Best regards!
Which of the following statements is false?
If a number is an integer, then it is irrational.
If a number is a natural number, then it is rational.
If a number is a fraction, then it is rational.
If a number is a whole number, then it is rational.
Answer:
If a number is an integer, then it is irrational. ⇒ false statement
Step-by-step explanation:
Let's check:
If a number is an integer, then it is irrational.
- incorrect, as all integers are rational
If a number is a natural number, then it is rational.
- correct, natural numbers are subset of rational numbers
If a number is a fraction, then it is rational.
- correct, they can be shown as p/q
If a number is a whole number, then it is rational.
- correct, whole numbers are subset of rational numbers
The statement "If a number is an integer, then it is irrational" is false.
Which of the following statements is false?The statement "If a number is an integer, then it is irrational" is false. This is because not all integers are irrational.
The other statements are all true:
"If a number is a natural number, then it is rational." This is true because all natural numbers are integers, and all integers are rational.
"If a number is a fraction, then it is rational." This is true because a fraction is a number of the form p/q, where p and q are integers and q is not equal to 0. Any number of this form is rational.
"If a number is a whole number, then it is rational." This is true because all whole numbers are integers, and all integers are rational.
Therefore, the false statement is the first one: "If a number is an integer, then it is irrational."
Below is a table summarizing the statements:
Statement Truth value
If a number is an integer, then it is irrational False
If a number is a natural number, then it is rational True
If a number is a fraction, then it is rational True
If a number is a whole number, then it is rational True
Learn more about rational numbers on:
brainly.com/question/22221295
#SPJ6
I dont understand this please help Which expression represents the area of the shaded region
Answer:
I'm gonna say C
The diameter of Earth’s moon is on average m. Use the formula to find the approximate surface area. (Use 3.14 for the value of .) (SHOW WORK)
Answer:
Surface Area = 4(3.14)((m/2)^2)
Step-by-step explanation:
The formula of surface area is 4(3.14)(r^2)
where r is the radius
We are given the diameter M which is just the radius times 2. So to find the radius we divide m by 2. So our radius is m/2.
(1-Cota)^2
+(tana-1)^2=4cosec2a(cosec2a-1)
Answer:
Step-by-step explanation:
(1-CotA)² + (tanA-1)² = 4csc2A(csc2A-1)
To prove this equation we will take the expression given in left hand side and will convert it into the expression given in right hand side of the equation.
L.H.S. = (1-CotA)² + (tanA-1)²
= 1 + Cot²A - 2CotA + 1 + tan²A - 2tanA
= cosec²A - 2CotA + Sec²A - 2tanA
[Since, (1 + Cot²A = cosec²A) and (1 + tan²A = Sec²A)]
= (cosec²A + Sec²A) - 2(CotA + tanA)
= [tex](\frac{1}{\text{SinA}})^{2}+(\frac{1}{CosA} )^{2}-2\text{(tanA}+\frac{1}{\text{tanA}})}[/tex]
= [tex]\frac{1}{(\text{SinA.CosA})^2}-2(\frac{tan^2A+1}{tanA} )[/tex]
= [tex]\frac{4}{\text{(Sin2A})^{2}}-4(\frac{1}{\text{Sin2A}} )[/tex]
[Since 2SinA.CosA = Sin2A and [tex]\frac{2(\text{tanA})}{1+\text{tan}^{2}A}=\text{Sin2A}[/tex]]
= 4Cosec²2A - 4Cosec2A
= 4Cosec2A(Cosec2A - 1)
= R.H.S. (Right hand side)
Hence the equation is proved.
Write a rational number in fraction form that is equivalent to -1.\overline{5}
Answer:
[tex]\dfrac{-14}{9}[/tex].
Step-by-step explanation:
The given number is [tex]-1.\overline{5}[/tex].
We need to find a rational number in fraction form that is equivalent to given number.
Let [tex]x=-1.\overline{5}[/tex]
[tex]x=-1.555...[/tex] ...(1)
Multiply both sides by 10.
[tex]10x=-15.555...[/tex] ...(2)
Subtracting (1) from (2), we get
[tex]10x-x=-15.555...-(-1.555...)[/tex]
[tex]9x=-14[/tex]
Divide both sides by 9.
[tex]x=\dfrac{-14}{9}[/tex]
Therefore, the required rational number is [tex]\dfrac{-14}{9}[/tex].
A cardboard box without a lid is to be made with a volume of 4 ft 3 . Find the dimensions of the box that requires the least amount of cardboard.
Answer:
2ft by 2ft by 1 ftStep-by-step explanation:
Total surface of the cardboard box is expressed as S = 2LW + 2WH + 2LH where L is the length of the box, W is the width and H is the height of the box. Since the cardboard box is without a lid, then the total surface area will be expressed as;
S = lw+2wh+2lh ... 1
Given the volume V = lwh = 4ft³ ... 2
From equation 2;
h = 4/lw
Substituting into r[equation 1;
S = lw + 2w(4/lw)+ 2l(4/lw)
S = lw+8/l+8/w
Differentiating the resulting equation with respect to w and l will give;
dS/dw = l + (-8w⁻²)
dS/dw = l - 8/w²
Similarly,
dS/dl = w + (-8l⁻²)
dS/dw = w - 8/l²
At turning point, ds/dw = 0 and ds/dl = 0
l - 8/w² = 0 and w - 8/l² = 0
l = 8/w² and w =8/l²
l = 8/(8/l² )²
l = 8/(64/I⁴)
l = 8*l⁴/64
l = l⁴/8
8l = l⁴
l³ = 8
l = ∛8
l = 2
Hence the length of the box is 2 feet
Substituting l = 2 into the function l = 8/w² to get the eidth w
2 = 8/w²
1 = 4/w²
w² = 4
w = 2 ft
width of the cardboard is 2 ft
Since Volume = lwh
4 = 2(2)h
4 = 4h
h = 1 ft
Height of the cardboard is 1 ft
The dimensions of the box that requires the least amount of cardboard is 2ft by 2ft by 1 ft
Because she has limited shelf space, she can't put out all her copies of the CD at once. On Monday morning, she stocked the display with 40 copies. By the end of the day, some of the copies had been sold. On Tuesday morning, she counted the number of copies left and then added that many more to the shelf. In other words, she doubled the number that was left in the display. At the end of the day, she discovered that she had sold the exact same number of copies as had been sold on Monday. On Wednesday morning, the manager decided to triple the number of copies that had been left in the case after Tuesday. Amazingly, she sold the same number of copies on Wednesday as she had on each of the first two days! But this time, at the end of the day the display case was empty.
Now, it look like there is some information missing in the answer. The whole problem should look like this:
Alicia Keys's new album As I Am is climbing the charts, and the manager of Tip Top Tunes expects to sell a lot of copies. Because she has limited shelf space, she can't put out all her copies of the CD at once. On Monday morning, she stocked the display with 40 copies. By the end of the day, some of the copies had been sold. On Tuesday morning, she counted the number of copies left and then added that many more to the shelf. In other words, she doubled the number that was left in the display. At the end of the day, she discovered that she had sold the exact same number of copies as had been sold on Monday. On Wednesday morning, the manager decided to triple the number of copies that had been left in the case after Tuesday. Amazingly, she sold the same number of copies on Wednesday as she had on each of the first two days! But this time, at the end of the day the display case was empty. How many copies of the As I Am CD did she sell each day?
Answer:
She sold 24 copies of the cd each day.
Step-by-step explanation:
In order to solve this problem we must first set our variable up. In this case, since we need to know what the number of sold cd's per day is, that will just be our variable:
x= Number of copies sold.
So we can start setting our equation up. So we take the first part of the problem:
"On Monday morning, she stocked the display with 40 copies. By the end of the day, some of the copies had been sold."
This can be translated as:
40-x
where this expression represents the number of copies left on the shelf by the end of monday.
"On Tuesday morning, she counted the number of copies left and then added that many more to the shelf."
so we represent it like this:
(40-x)+(40-x)
"In other words, she doubled the number that was left in the display."
so the previous expression can be simplified like this:
2(40-x)
"At the end of the day, she discovered that she had sold the exact same number of copies as had been sold on Monday."
so the expression now turns to:
2(40-x)-x this is the number of copies left by the end of tuesday.
"On Wednesday morning, the manager decided to triple the number of copies that had been left in the case after Tuesday."
this translates to:
3[2(40-x)-x]
This is the number of copies on the shelf by the begining of Wednesday.
"Amazingly, she sold the same number of copies on Wednesday as she had on each of the first two days! But this time, at the end of the day the display case was empty."
this piece of information lets us finish writting our equation:
3[2(40-x)-x] -x = 0
since there were no copies left on the shelf, then the equation is equal to zero.
So now we proceed and solve the equation for x:
3[2(40-x)-x] -x = 0
We simplify it from the inside to the outside.
3[80-2x-x]-x=0
3[80-3x]-x = 0
we now distribute the 3 so we get:
240-9x-x=0
we combine like terms so we get:
240-10x=0
we move the 240 to the other side of the equation so we get:
-10x=-240
and divide both sides into -10 so we get:
x=24
so she sold 24 copies each day.
Please answer this correctly without making mistakes
Answer: 139/7
Step-by-step explanation:
Answer:
139/7
Step-by-step explanation:
182/10 = 18.2 < 18 7/11
219/12 = 18 + 3/12 = 18 1/4 < 18 7/11
139/7 = 19 + 4/7 > 18 7/11
179/10 = 17.9 < 18 7/11
