Answer:
i think
x=6.77
y=11.33
Billy has x marbles. Write an expression for the number of marbles the following have… a) Charlie has 5 more than Billy b) Danny has 8 fewer than Billy c) Eric has three times as many as Billy
Answer:
Charlie: 5 + xDanny: x - 8Eric: x × 3If there are 80 students in a class and 20 are seniors, what proportion of students are not seniors?
Answer:
3/4
Step-by-step explanation:
First find the number that are not seniors
80 -20 = 60
60 are not seniors
The ratio of not seniors to total
60/80
Divide top and bottom by 20
3/4
Answer:
60 students
Step-by-step explanation:
80 -20 = 60
A publishing company claims that in fall 2019, the average price of college textbooks for a single semester is $385. Suppose you decide to collect data from a random sample of students to assess whether the publisher's claim is reasonable, and you find that in a random sample of 22 college students, the mean price of textbooks for the fall 2019 semester was $433.50 with a standard deviation of $86.92. At the 0.01 significance level, is there sufficient evidence to conclude that the mean price of college textbooks for a single semester is different from the value claimed by the publisher?
Answer:
We accept H₀ . We don´t have enough evidence to express the publisher claim is not true
Step by Step explanation:
We must evaluate if the mean of the price of college textbooks is different from the value claimed by the publisher
n < 30 then we must use t - distrbution
degree of freedom n - 1 df = 22 - 1 df = 21
As the question mentions " different " that means, a two-tail test
At 0,01 significance level α = 0,01 α/2 = 0,005
and t(c) = 2,831
Test Hypothesis
Null Hypothesis H₀ μ = μ₀
Alternative hypothesis Hₐ μ ≠ μ₀
To calculate t(s)
t(s) = ( μ - μ₀ ) /σ/√n
t(s) = ( 433,50 - 385 ) / 86,92 / √22
t(s) = 2,6171
Comparing t(c) and t(s)
t(s) < t(c)
Then t(s) is in the acceptance region we accept H₀. We don´t have enough evidence to claim that mean price differs from publisher claim
Identify the recursive formula for the sequence given by the explicit formula f(n) = 20 – 4(n − 1).
Answer:
[tex]\huge\boxed{f(n)=\left\{\begin{array}{ccc}f(1)=20\\f(n)=f(n-1)-4\end{array}\right}[/tex]
Step-by-step explanation:
[tex]f(n)=20-4(n-1)=20+(n-1)(-4)\\\\\text{It's an explicit formula of an arithmetic sequence:}\\\\f(n)=a_1+(n-1)(d)\\\\a_1-\text{first term}\\d-\text{common difference}\\\\\text{Conclusion:}\\\text{Next term}=\text{previous one}\ -4\\\\\text{The recursive formula:}\\\\\huge\boxed{f(n)=\left\{\begin{array}{ccc}f(1)=20\\f(n)=f(n-1)-4\end{array}\right}[/tex]
Answer:
Step-by-step explanation:
someone answered already
Enclosing the Largest Area The owner of the Rancho Grande has 3,052 yd of fencing with which to enclose a rectangular piece of grazing land situated along the straight portion of a river. If fencing is not required along the river, what are the dimensions (in yd) of the largest area he can enclose
Answer:
the shorter side = 1526
the longer side = 763
area = 1164338
Step-by-step explanation:
lets say
a=length
b = width
a + 2b = 3052
this is the perimeter
such that
a = 3052 - 2b
the area of a rectangle is a*b
= (3052 - 2b)b
= 3052b - 2b²
we differentiate this to get:
= 3052 - 4b
such that
3052 = 4b
divide through by 4, to get b, the width
3052/4 = 763
b = 763
put the value of b into a
a = 3052 - 2b
a = 3052 - 2(763)
a = 3052 - 1526
a = 1526
therefore
the shorter side = 1526
the longer side = 763
area = a x b
area = 1526 x 763
area = 1526 x 763
= 1164338
What is the equation of the parabola that has its vertex at (8,-1) and a y-intercept of (0,-17)?
y = a(x + 1.5)^2 - 12.5
y intercept is (0,-8) so:-
-8 = a(0+1.5)^2 - 12.5
-8 = 2.25a - 12.5
a = 4.5/ 2.25 = 2
so we have
y = 2 ( x +1.5)^2 - 12.5
solving for x when y = 0:-
(x + 1.5)^2 = 12.5/2 = 6.25
taking sqrt's x + 1.5 = +/- 2.5
x = -4, 1
so the x intercepts are (-4,0) and (1,0)
Answer:
y = –1∕4(x – 8)^2 – 1
Step-by-step explanation:
I took the exam and got it right.
The population of men at UMBC has a mean height of 69 inches with a standard deviation of 4 inches. The women at UMBC have a mean height of 65 inches with a standard deviation of 3 inches. A sample of 50 men and 40 women is selected. What is the probability that the sample mean of men heights is more than 5 inches greater than the sample mean of women heights
Answer:
The probability that the sample mean of men heights is more than 5 inches greater than the sample mean of women heights is 0.0885.
Step-by-step explanation:
We are given that the population of men at UMBC has a mean height of 69 inches with a standard deviation of 4 inches. The women at UMBC have a mean height of 65 inches with a standard deviation of 3 inches.
A sample of 50 men and 40 women is selected.
The z-score probability distribution for the two-sample normal distribution is given by;
Z = [tex]\frac{(\bar X_M-\bar X_W)-(\mu_M-\mu_W)}{\sqrt{\frac{\sigma_M^{2} }{n_M}+\frac{\sigma_W^{2} }{n_W} } }[/tex] ~ N(0,1)
where, [tex]\mu_M[/tex] = population mean height of men at UMBC = 69 inches
[tex]\mu_W[/tex] = population mean height of women at UMBC = 65 inches
[tex]\sigma_M[/tex] = standard deviation of men at UMBC = 4 inches
[tex]\sigma_M[/tex] = standard deviation of women at UMBC = 3 inches
[tex]n_M[/tex] = sample of men = 50
[tex]n_W[/tex] = sample of women = 40
Now, the probability that the sample mean of men heights is more than 5 inches greater than the sample mean of women heights is given by = P([tex]\bar X_M-\bar X_W[/tex] > 5 inches)
P([tex]\bar X_M-\bar X_W[/tex] > 5 inches) = P( [tex]\frac{(\bar X_M-\bar X_W)-(\mu_M-\mu_W)}{\sqrt{\frac{\sigma_M^{2} }{n_M}+\frac{\sigma_W^{2} }{n_W} } }[/tex] > [tex]\frac{(5)-(69-65)}{\sqrt{\frac{4^{2} }{50}+\frac{3^{2} }{40} } }[/tex] ) = P(Z > 1.35)
= 1 - P(Z [tex]\leq[/tex] 1.35) = 1 - 0.9115 = 0.0885
The above probability is calculated by looking at the value of x = 1.35 in the z table which has an area of 0.9115.
HELP PLZ A circle inscribed in a triangle:
Answer:
The answer is the second photo.
Step-by-step explanation:
It's literally a circle in a triangle. So, it's the second one.
The circumference of a sphere was measured to be 82 cm with a possible error of 0.5 cm.
A. Use differentials to estimate the maximum error in the calculated volume.
What is the relative error?
B. Use differentials to estimate the maximum error in the calculated volume.
What is the relative error?
Answer:
A) Maximum error = 170.32 cm³
B)Relative error = 0.0575
Step-by-step explanation:
A) Formula for circumference is: C = 2πr
Differentiating with respect to r, we have;
dC/dr = 2π
r is small, so we can write;
ΔC/Δr = 2π
So, Δr = ΔC/2π
We are told that ΔC = 0.5.
Thus; Δr = 0.5/2π = 0.25/π
Now, formula for Volume of a sphere is;
V(r) = (4/3)πr³
Differentiating with respect to r, we have;
dV/dr = 4πr²
Again, r is small, so we can write;
ΔS/Δr = 4πr²
ΔV = 4πr² × Δr
Rewriting, we have;
ΔV = ((2πr)²/π) × Δr
Since C = 2πr, we now have;
ΔV = (C²/π)Δr
ΔV will be maximum when Δr is maximum
Thus, ΔV = (C²/π) × 0.25/π
C = 82 cm
Thus;
ΔV = (82²/π) × 0.25/π
ΔV = 170.32 cm³
B) Formula for relative error = ΔV/V
Relative error = 170.32/((4/3)πr³)
Relative error = 170.32/((4/3)C³/8π³)
Relative errror = 170.32/((4/3)82³/8π³)
Relative error = 170.32/2963.744
Relative error = 0.0575
Ava placed the point of her pencil on the origin of a regular coordinate plane. She marked a point after moving her pencil 4 units to the left and 7 units up. Which ordered pair identifies where Ava marked her point?
[tex] \Large{ \boxed{ \bold{ \color{lightgreen}{Solution:}}}}[/tex]
So, Let's solve this question by using cartesian plane.
Here, Origin is shown by (0, 0)Ava moves 4 units left from origin. On the left side of origin, negative x axis begins. So, she reached (-4, 0) now.Then, from that point she moved 7 units upwards. On the upper side, there is positive y axis. So, Finally she will reach point (-4, 7).(-4, 7) is the coordinate of point which is 4 units left from y axis and 7 units up from x axis.It lies on the second quadrant.Well, What is cartesian plane?
A - A Cartesian coordinate system is a coordinate system that specifies each point uniquely in a plane by a set of numerical coordinates, which are the signed distances to the point from two fixed perpendicular oriented lines, measured in the same unit of length.
━━━━━━━━━━━━━━━━━━━━
the bold answer is incorrect. what is the right answer?
What is 32 divided by the opposite of 4
Answer: -8
Since we are dividing the OPPOSITE of 4 then we are dividing 32÷-4
When multiplying or dividing a POSITIVE to a NEGATIVE you get a NEGATIVE
P/N=N
N/N=P
P*P=P
P=Positive
N=Negative
Divide
32/-4=-8
So your answer is -8
When 32 is divided by opposite of 4 the obtained result is - 8.
What is additive inverse ?Additive inverse of a number is such a number when the original number and it's additive inverse is added we get zero.
4 + ( - 4 ) = 0.So the additive inverse of 4 is - 4.
According to the given question we have to obtain the result when 32 is divided by opposite of 4.
Here opposite of 4 means additive inverse of 4 which is -4.
∴ 32/-4
= - 8.
learn more about additive inverse here :
https://brainly.com/question/13715269
#SPJ2
How long will it take $3800 to grow into $5700 if it’s invested at 6% interest compounded continuously?
Answer: 25 years
Step-by-step explanation:
t = I / Pr
t = 5700 / ( 3800 × 0.06 ) = 25
t = 25 years
What is the volume of a square pyramid whose length of one side of its base is 9cm and whose height is 15cm. Show your work
Answer:
The answer is 405cm³Step-by-step explanation:
Volume of a pyramid is given by
[tex]V = \frac{1}{3} \times area \: of \: base \: \: \times height[/tex]
height = 15cm
From the question the pyramid is a square pyramid which means it's base is a square
Area of a square = l²
where l is the length of one side
l = 9cm
Area of square = 9² = 81cm²
So the volume of the pyramid is
[tex]V = \frac{1}{3} \times 81 \times 15[/tex]
[tex]V = 27 \times 15[/tex]
We have the final answer as
V = 405 cm³
Therefore the volume of the pyramid is
405cm³Hope this helps you
Which of the following is the correct notation of the complex number?
Answer:
-84 + 10i
Step-by-step explanation:
Standard Complex Form: a + bi
Step 1: Evaluate
√-100 = √-1 x √100 = i x 10 = 10i
-84 = -84
Step 2: Combine
10i - 84
Step 3: Rearrange
-84 + 10i
Answer:
Last Option
Step-by-step explanation:
√-100 - 84
(√(100×-1)) - 84
(√100)(√-1)-84
√-1 = i
10i - 84 or -84 + 10i
I need help ? which linear function is represented by the graph?
=================================================
Explanation:
The diagonal line passes through 1 on the vertical y axis. So the y intercept is b = 1. This means the location of the y intercept is (0,1).
Start at (0,1) and move down 1 and to the right 2 to arrive at (2,0). This is another point on the diagonal line. The motion of "down 1 and right 2" is effectively the slope
slope = rise/run = -1/2
rise = -1, run = 2
The rise being negative means we have gone downhill as we move to the right.
With m = -1/2 as the slope and b = 1 as the y intercept, we go from y = mx+b to y = (-1/2)x+1
The last thing to do is replace y with f(x) to get f(x) = (-1/2)x+1 as the final answer.
Answer:
it's b
Step-by-step explanation:
b
If the weight (in grams) of cereal in a box of Lucky Charms is N(470,5), what is the probability that the box will contain less than the advertised weight of 453 g?
Answer:
The probability that the box will contain less than the advertised weight of 453 g is 0.00034.
Step-by-step explanation:
Let X represent the weight (in grams) of cereal in a box of Lucky Charms.
It is provided that X follows a Normal distribution with parameters, μ = 470 and σ = 5.
Compute the probability that the box will contain less than the advertised weight of 453 g as follows:
[tex]P(X<453)=P(\frac{X-\mu}{\sigma}<\frac{453-470}{5})[/tex]
[tex]=P(Z<-3.4)\\=0.00034[/tex]
*Use the z-table.
Thus, the probability that the box will contain less than the advertised weight of 453 g is 0.00034.
Line MN passes through points M(4, 3) and N(7, 12). If the equation of the line is written in slope-intercept form, y = mx + b, what is the value of b? –15 –9 3 9
Answer:
b = -9.
Step-by-step explanation:
The line passes through (4, 3) and (7, 12). First, we need to find the slope: the rise over the run.
(12 - 3) / (7 - 4) = 9 / 3 = 3.
Now that we have the slope, we can say that m = 3. So, we have an equation of y = 3x + b. To find b, we can use M(4, 3) and say that y = 3 and x = 4.
3 = 3 * 4 + b
b + 12 = 3
b = -9.
Hope this helps!
The value of b in the equation is -9
How to determine the value of b?The points are given as:
M(4, 3) and N(7, 12)
The equation is then calculated using:
[tex]y = \frac{y_2 -y_1}{x_2 -x_1} * (x - x_1) + y_1[/tex]
This gives
[tex]y = \frac{12 -3}{7 -4} * (x - 4) + 3[/tex]
Evaluate the quotient
y = 3 * (x - 4) + 3
Open the bracket
y = 3x - 12 + 3
Evaluate the difference
y = 3x - 9
Hence, the value of b is -9
Read more about linear equations at:
https://brainly.com/question/14323743
#SPJ9
Use the frequency distribution, which shows the number of American voters (in millions) according to age, to
find the probability that a voter chosen at random is in the 18 to 20 years old age range
Ages
18 to 20
21 to 24
25 to 34
35 to 44
45 to 64
65 and over
Frequency
4.2
7.8
20.8
23.7
50.1
28 2
Date
07/2
3:29
The probability that a voter chosen at random is in the 18 to 20 years old age range is 0.0311
(Round to three decimal places as needed.)
07/2
8:52
Question Viewer
07/1
8:03
07/1
5:46
>
07/1
12:2
07/1
5:39
07/1
2:42
Question is complete. Tap on the red indicators to see incorrect answers.
07/1
12:00
Answer:
The probability that a voter chosen at random is in the 18 to 20 years old age range is = 4.2/ 134.8= 0.0311572
Step-by-step explanation:
We can find the probability by simply dividing the frequency of the ages range of 18-20 by the total frequency.
Ages Frequency
18 to 20 4.2
21 to 24 7.8
25 to 34 20.8
35 to 44 23.7
45 to 64 50.1
65 and over 28.2
∑ 134.8
The probability of an event is given by the occurrence of an event by the total occurrences .
So
Here the occurrence of ages 18-20 is given by 4.2
and the total frequency is 134.8
The probability that a voter chosen at random is in the 18 to 20 years old age range is = 4.2/ 134.8= 0.0311572
Which phrase describes the algebraic expression 8f+7?
the product of 8 and 7 more than a number
the quotient of 8 and 7
8 times the sum of a number and 7
8 times a number plus 7
Answer:
8 times a number plus 7
Step-by-step explanation:
Let the number be f.
Simply, 8 f+7 is the expression.
Thank you!
Can I have somebody answer a few more of the questions that I need please and this one too?
Answer:
x > 22
Step-by-step explanation:
Hey there!
Well to solve,
52 - 3x < -14
we need to single out x
52 - 3x < -14
-52 to both sides
-3x < -66
Divide both sides by -3
x > 22
The < changes to > because the variable number is a - being divided.
Hope this helps :)
Answer:
x > 22
Step-by-step explanation:
First, rearrange the equation
52 - 3 × x - (-14) < 0Then, pull out the like terms:
66 - 3xNext, apply algebra to the equation by dividing each side by -3. It should now look like this: x > 22.
Therefore, the solution set of the inequality would be x > 22.
2/5(10c -35) (the 35 is negative)
Answer:
The simplified form is 2 (c - 7).
Step-by-step explanation:
The expression to be solved is:
[tex]f (c)=\frac{2}{5} (10c -35)[/tex]
Simplify the expression as follows:
[tex]f (c)=\frac{2}{5} (10c -35)[/tex]
[tex]=[\frac{2}{5}\times 10c]-[\frac{2}{5}\times 35]\\\\=[2\times 2c]-[2\times 7]\\\\=4c-14\\\\=2(c-7)[/tex]
Thus, the simplified form is 2 (c - 7).
Rational equation of 3/x+1=2/x-3
Answer:
x = 11
Step-by-step explanation:
3/x+1=2/x-3
Solve by using cross products
2 (x+1) = 3 (x-3)
Distribute
2x+2 = 3x-9
Subtract 2x
2x+2-2x = 3x-2x-9
2 = x-9
Add 9 to each side
2+9 =x-9+9
11 =c
Joey’s pizza sells large cheese pizzas for $12.00. Each additional topping costs $0.50. Basketball Boosters bought 12 large pizzas, each with 3 toppings. There are 8 slices per pizza. How much does it cost per slice? Round to the nearest cent.
Answer:
So first you do $0.50 x 3 = 1.5
then you add that to $12.00
$12.00 + 1.5 = 13.5
13.5 is the cost of one pizza.
Since they bought 12:
The total cost of the 12 pizza is $162 <== not important
13.5 divided by 8 is 1.687
round 1.56875 to the nearest cent 1.7 = $2
so each slice costs $2
PLEASE HELP QUICK!!!!!!! Find the length of a rectangle that has one side of length 8 and area 32
Answer:
4
Step-by-step explanation:
Length of one side=8
Area=32
Length of another side=x
8 into x = 32
X=32/8
=4
If the nth term is , then the (n+1)st is: Please make sure you check the image :)
Answer:
( n+1) /2 *( 3n+2)
Step-by-step explanation:
n/2 * ( 3n-1)
We want the n+1 term
Replace n with n+1
( n+1) /2 *( 3( n+1) -1)
Distribute
( n+1) /2 *( 3n+3 -1)
( n+1) /2 *( 3n+2)
Answer:
[tex]\large \boxed{\sf C. \ \frac{n+1}{2} (3n+2)}[/tex]
Step-by-step explanation:
[tex]\displaystyle \frac{n}{2} (3n-1)[/tex]
To find the (n+1)st term, replace the n variable with n+1.
[tex]\displaystyle \frac{n+1}{2} (3(n+1)-1)[/tex]
Expand brackets.
[tex]\displaystyle \frac{n+1}{2} (3n+3-1)[/tex]
Subtract like terms in brackets.
[tex]\displaystyle \frac{n+1}{2} (3n+2)[/tex]
A certain game involves tossing 3 fair coins, and it pays .14 for 3 heads, .06 for 2 heads, and .01 for 1 head. The expected winnings are?
Answer:
Total expected amount = $0.04375
Step-by-step explanation:
We need to calculate probability of getting heads on every combination of coin tosses
HHH = 1/8 = 3 heads
HHT = 1/8 = 2 heads
HTH = 1/8 = 2 heads
HTT = 1/8 = 1 head
THH = 1/8 = 2 heads
THT = 1/8 = 1 head
TTH = 1/8 = 1 head
TTT = 1/8 = 0 head
So the probability of 3 heads is 1/8 and the amount is (1/8)* 0.14 = $0.0175
Probability of 2 heads is 3/8 and the amount is (3/8) * 0.06 = $0.0225
Probability of 1 head is 3/8 and amount is (3/8) * 0.01 = $0.00375
Total expected amount = 0.00375 + 0.0225 + 0.0175
Total expected amount = $0.04375
Use the dot product to determine whether v and w are orthogonal.
v=-i-j, w=-i+j
Select the correct choice below and fill in the answer box to complete your choice.
O A. The vectors v and w are not orthogonal because their dot product is ___
O B. The vectors v and w are orthogonal because their dot product is ___
Answer:
B. The vectors v and w are orthogonal because their dot product is 0
Step-by-step explanation:
Given that :
v= - i - j
w= - i + j
Therefore;
vw = ( - i - j ) ( - i + j )
Taking each set of integer of the vector into consideration:
vw = ( -1 × - 1) ( -1 × 1)
vw = 1 - 1
vw = 0
Hence, we can conclude that :
The vectors v and w are orthogonal because their dot product is 0
a company should stop making a part internally and buy externally when
Answer:
Make-or-Buy Decision
Step-by-step explanation:
2. Write the equation of the circle in general form. Show your work.
Answer:
[tex] {(x + 1)}^{2} + {(y - 1)}^{2} = 9[/tex]
[tex] {x} ^{2} + {y} ^{2} + 2x - 2y - 7 = 0 [/tex]