Answer:
$4.50
Step-by-step explanation:
Use the mean formula: mean = sum of elements / number of elements
Let x represent the cost of the fifth book, and solve for x:
mean = sum of elements / number of elements
3.25 = (11.75 + x) / 5
16.25 = 11.75 + x
4.5 = x
So, the cost of the fifth book was $4.50
A trough is 10 ft long and its ends have the shape of isosceles triangles that are 4 ft across at the top and have a height of 1 ft. If the trough is being filled with water at a rate of 15 ft3/min, how fast is the water level rising when the water is 8 inches deep
Answer:
7.5 ft³/min
Step-by-step explanation:
Let x be the depth below the surface of the water. The height, h of the water is thus h = 10 - x.
Now, the volume of water V = Ah where A = area of isosceles base of trough = 1/2bh' where b = base of triangle = 4 ft and h' = height of triangle = 1 ft. So, A = 1/2 × 4 ft × 1 ft = 2 ft²
So, V = Ah = 2h = 2(10 - x)
The rate of change of volume is thus
dV/dt = d[2(10 - x)]/dt = -2dx/dt
Since dV/dt = 15 ft³/min,
dx/dt = -(dV/dt)/2 = -15 ft³/min ÷ 2 = -7.5 ft³/min
Since the height of the water is h = 10 - x, the rate at which the water level is rising is dh/dt = d[10 - x]/dt
= -dx/dt
= -(-7.5 ft³/min)
= 7.5 ft³/min
And the height at this point when x = 8 inches = 8 in × 1 ft/12 in = 0.67 ft is h = (10 - 0.67) ft = 9.33 ft
A wheelchair ramp with a length of 61 inches has a horizontal distance of 60 inches. What is the ramp’s vertical distance
Answer:
Step-by-step explanation:
The solution triangle attached below :
Since we have a right angled triangle, we can make use of Pythagoras rule to obtain the vertical distance, x
Recall :
Hypotenus² = opposite² + adjacent²
Hence,
x² = 61² - 60²
x² = 3721 - 3600
x² = 121
x = √121
x = 11
Vertical distance equals 11 inches
add 10ft 3in + 3ft 9in + 8ft 10in
3s + 4t = 22
8s + 8t = 48
What is s and what is t
(Similtaneous Equations)
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Answer:
(s, t) = (2, 4)
Step-by-step explanation:
We can eliminate the t variable by subtracting the first equation from half the second.
(1/2)(8s +8t) -(3s +4t) = (1/2)(48) -(22)
s = 2
3(2) +4t = 22
4t = 16
t = 4
The solution is (s, t) = (2, 4).
One way to check on how representative a survey is of the population from which it was drawn is to compare various characteristics of the sample with the population characteristics. A typical variable used for this purpose is age. The 2010 GSS of the American adult population found a mean age 49.28 years and a standard deviation of 17.21 for its sample of 4,857 adults. Assume that we know from Census data that the mean age of all American adults is 37.2 years.
Required:
a. State the research and the null hypothesis setting for a two-tailed test.
b. Calculate the t statistics and test the null hypothesis setting alpha at .01. What did you find?
c. What is your decision about the null hypothesis? What does this tell us about how representative the sample is of the American adult population?
Answer:
a) See step by Step explanation
b) z(s) = 48.88
c) We reject H₀. The sample is not representative of American Adult Population
Step-by-step explanation:
From sample
sample mean . x = 49.28
sample standard deviationn s = 17.21
sample size n₁ = 4857
Population mean according to Census data
μ = 37.2
a) Test Hypothesis
Null Hypothesis . H₀ . x = μ = 37.2
Alternative Hypothesis Hₐ . x ≠ μ
b) We have sample size (4857) we can use normal distribution
z (c) for α = 0.01 α/2 . = 0.005 is from z-table . z(c) = 2.575
To calculate z(s) = ( x - μ ) / s /√n
z(s) = 12.08 * √4857 / 17.21
z(s) = 12.08* 69.64 / 17.21
z(s) = 48.88
z(s) > z(c)
We should reject H₀. The sample is not representative of American Adult population
Determine which statements about the relationship are true. Choose two options. g is the dependent variable. u is the dependent variable. g is the independent variable. u is the independent variable. The two variables cannot be labeled as independent or dependent without a table of values.
Answer:
1) g is the dependent variable.(A)
2) u is the independent variable.(D)
Step-by-step explanation:
A film distribution manager calculates that 9% of the films released are flops. If the manager is right, what is the probability that the proportion of flops in a sample of 469 released films would be greater than 6%
Answer:
0.9884 = 98.84% probability that the proportion of flops in a sample of 469 released films would be greater than 6%.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
A film distribution manager calculates that 9% of the films released are flops.
This means that [tex]p = 0.09[/tex]
Sample of 469
This means that [tex]n = 469[/tex]
Mean and standard deviation:
[tex]\mu = p = 0.09[/tex]
[tex]s = \sqrt{\frac{p(1-p)}{n}} = \sqrt{\frac{0.09*0.91}{469}} = 0.0132[/tex]
What is the probability that the proportion of flops in a sample of 469 released films would be greater than 6%?
1 subtracted by the p-value of Z when X = 0.06. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{0.06 - 0.09}{0.0132}[/tex]
[tex]Z = -2.27[/tex]
[tex]Z = -2.27[/tex] has a p-value of 0.0116
1 - 0.0116 = 0.9884
0.9884 = 98.84% probability that the proportion of flops in a sample of 469 released films would be greater than 6%.
Please help
Find the value of x,
m∠5 = x-6, m∠4 = 2x+4, m∠2 = 2x-26
urdxvjok NCAA earth bno
Help please!!!!!!!!!!!
Answer:
AB IS THE ANSWER !!!!!!!!!!
Answer: AB
Step-by-step explanation:
Hi! I don't know if you need help anymore ,but here you go!
Because BC=ED, I asume that AE=AB
solve the following system of equations with the help of matrix ::. x-2y-4=0 & -3x+5y+7=0
Answer:
(x, y) = (-34,-19)
Step-by-step explanation:
...................................................
The following data were obtained from 4 people Pre-Test Value Post-test Value 43 42 28 29 31 30 28 25 You may also assume that the sample standard deviation for the four differences is 1.6. What is the correct t-statistic and the degrees of freedom for these data
Answer:
Test statistic = 1.25
Degree of freedom = 3
Step-by-step explanation:
The following data were obtained from 4 people
Pre-Test Value Post-test Value __ d
43 ________42 _________ 1
28_______ 29 ________ - 1
31 ________30 _________ 1
28 ________ 25 _________ 3
μd = (1 + - 1 + 1 + 3) / 4 = 4 /4 = 1
The mean difference, μd = 1
The standard deviation of difference, Sd = 1.6
The test statistic = μd / (Sd / √n)
Test statistic = 1 / (1.6/2) = 1 / 0.8
Test statistic = 1.25
Degree of freedom, = n - 1 = 4 - 1 = 3
if sine Theta is less than 0 and tan Theta is greater than 0 then
Answer:
Sine Theta is a negative number, Tan Theta is a greater number then zero.
Step-by-step explanation:
If Sine Theta is less then zero, she is a negative number. So 0 - y = -y.
So if Tan Theta is a greater number than zero, her number is not negative. So 0 + y = y
I hope this helped! I didn’t really understand the question though.
Someone please help me ASAP!
Answer:
The 3rd
Step-by-step explanation:
If x goes to infinity, f(x) goes to infinity too:
[tex]lim \: \frac{2 {x}^{2} }{3x - 1} = lim \frac{2x}{3 - \frac{1}{x} } = \frac{ 2 \times \infty }{3 - 0} = \infty [/tex]
Express these system specifications using the propositions p “The user enters
a valid password,” q “Access is granted,” and r “The user has paid the
subscription fee” and logical connectives (including negations).
a) “The user has paid the subscription fee, but does not enter a valid
password.”
b) “Access is granted whenever the user has paid the subscription fee and
enters a valid password.”
c) “Access is denied if the user has not paid the subscription fee.”
d) “If the user has not entered a valid password but has paid the subscription
fee, then access is granted.”
Answer:
a) r ⋀~p
b)(r⋀p)⟶q
c) ~r ⟶ ~q
d) (~p ⋀r) ⟶q
Step-by-step explanation:
To solve this question we will make use of logic symbols in truth table.
We are told that;
p means "The user enters
a valid password,”
q means “Access is granted,”
r means “The user has paid the
subscription fee”
A) The user has paid the subscription fee, but does not enter a valid
password.”
Fist part of the statement is correct and so it will be "r". Second part of the statement is a negation and will be denoted by ~p. Since both statements are joined together in conjunction, we will use the conjuction symbol in between them which is "⋀" Thus, we have; r ⋀~p
B) Still using logic symbols, we have;
(r⋀p)⟶q
⟶ means q is true when r and p are true.
C) correct symbol is ~r ⟶ ~q
Since both statements are negation of the question. And also, if ~r is true then ~q is also true.
D) Similar to answer A to C above, applying similar conditions, we have (~p ⋀r) ⟶q
Find the volume of the figure. Express answers in terms of t, then round to the nearest whole number
Please help :)
Answer:
729π ft³
Step-by-step explanation:
Applying,
Volume of a cone
V = πr²h/3.............. Equation 1
Where r = radius of the base, h = height, π = pie
From the question,
Given: r = 9 ft, h = 27 ft
Substitite these values into equation 1
V = π(9²)(27)/3
V = 729π ft³
Hence the volume of the figure in terms of π is 729π ft³
Solutes in the bloodstream enter cells through a diffusion process called
osmosis, the diffusion of fluid through a semi-permeable membrane. Let C = C(t)
be the concentration of a certain solute inside a particular cell. The rate at which
the concentration inside the cell is changing is proportional to the difference in the
concentration of the solute in the bloodstream and the concentration within the cell.
Suppose the concentration of a solute in the bloodstream is maintained at a constant
level of L gm/cm?
(a) Write a differential equation involving
dc\dt
Answer:
en la calasa ni esta en la estacion
You have $1000 to invest in two different accounts. To save the money you need for college, you need to average 5.7 percent interest. If the two accounts pay 4 percent and 6 percent interest, how much should you invest in each account?
$550 in 4%, $450 in 6%
$300 in 4%, $700 in 6%
$700 in 4%, $300 in 6%
$150 in 4%, $850 in 6%
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Answer:
$150 in 4%, $850 in 6%
Step-by-step explanation:
The fraction that must earn the highest rate is ...
(5.7 -4.0)/(6.0 -4.0) = 1.7/2 = 0.85
That is 0.85 × $1000 = $850 must be invested at 6%. Matches the last choice.
_____
If you let x represent the amount that must earn 6%, then the total interest earned must be ...
x·6% +(1000 -x)·4% = 1000·5.7%
x(6 -4) = 1000(5.7 -4) . . . . . . multiply by 100, subtract 4·1000
x = 1000·(5.7 -4)/(6 -4) = 850 . . . . as above
Decreased by 0% is 800 ?
Find the negative reciprocal of the slope of the orginal line. Undefined
Answer:
800
Step-by-step explanation:
100%-0%=100%
100% is also equal to the number 1.
We now have 1x=800
Simplify that and get 800
The 2010 GSS provides the following statistics for the average years of education for lower-, working-, middle-, and upper-class respondents and their associated standard deviations. Assume that years of education are normally distributed in the population. Mean Standard Deviation N Lower-class 11.61 2.67 123 Working-class 12.80 2.85 697 Middle-class 14.45 3.08 626 Upper-class 15.45 2.98 38 How many years of education correspond to a Z score of +1.2 for upper-class respondents?
Answer:
The answer is "18.087 years".
Step-by-step explanation:
For upper class:
[tex]\mu=15.45 \ years\\\\\alpha=2.98 \ years\\\\[/tex]
[tex]P(Z \leq 1.2)[/tex] from the standard normal distribution on the table:
[tex]P(Z \leq 1.2) =0.8849\\\\x=z_{\alpha}+\mu\\\\[/tex]
[tex]=0.8849 \times 2.98 +15.45\\\\ = 2.637002+15.45 \\\\=18.087 \ \ years\\[/tex]
The volume of a pyramid is 240 cubic centimeters. The pyramid has a rectangular base with sides 6cm by 4cm. Find the altitude and lateral surface area of the pyramid if the pyramid has equal lateral edges
Answer:
altitude = 30 cm
lateral surface area = 301 cm² (approximately)
Step-by-step explanation:
let the altitude be x,
240=6*4*x/3
or, x=30 cm
Lateral surface area,
=l×√(w/2)²+h²]+w×√[(l/2)²+h²]
=6×√[(4/2)²+30²]+4×√[(6/2)²+30²]
≈300.99806
≈ 301 cm²
Answered by GAUTHMATH
SOLVE PLS!! ILL MARK BRAINILEST!!
Answer:
73.3333....
Step-by-step explanation:
please mark me brainliest
Answer:
a: t=13.6 cm
b: h=12.9 mm
Step-by-step explanation:
Hi there!
Let's start with a
in a, we are given a right triangle (notice the right angle), the length of the hypotenuse (the side OPPOSITE from the right angle) as 18 cm, one acute angle given as 41° and the length of one of the legs (the legs are the sides that make up the right angle) as t
We're asked to use the primary trigonometric ratios
Those ratios are:
Sine, which is opposite/hypotenuse
Cosine, which is adjacent/hypotenuse
Tangent, which is opposite/adjacent
We will be basing the ratio off of the 41° angle, so let's find out which sides will be which in reference to that angle
The opposite side will be the other leg, the unmarked side
The adjacent side will be t
The hypotenuse will be the side marked as 18 cm
So let's use cos(41) in this case
cos(41)=t/18
Plug cos(41) into your calculator, and remember to have the calculator in degree mode
cos(41)≈0.8 (rounded to the nearest tenth)
0.8=t/18
multiply both sides by 18
13.6 cm=t
It's already rounded to the nearest tenth :)
b.
We are given a right triangle, and the lengths of the legs as h and 9 mm, as well as one acute angle as 35°
We'll be basing our ratio off of the 35 degree angle, so let's find which sides will be which in reference to that angle
The opposite side will be the leg marked as 9 mm
The adjacent side will be the leg marked as h
The hypotenuse will be the unmarked side
Since we are given the lengths of the opposite and the adjacent, let's use tan(35)
tan(35)=9/h
Plug tan(35) into your calculator, and remember to have it in degree mode
tan(35)≈0.7
0.7=9/h
multiply both sides by h
0.7h=9
divide both sides by 0.7
h=12.9 mm (rounded to the nearest tenth)
Hope this helps!
If one card is drawn from a deck, find the probability of getting these results.
Enter your answers as fractions or as decimals rounded to 3 decimal places.
Answer:
Face card= 12/52
(52 cards in a deck and 12 are face cards)
Red face card= 6/12
(12 face cards in a deck cards in a deck and 6 are red face cards)
Black face card= 6/52
(6 are black)
Black card= 26/52
(52 cards in a deck and 26 are black)
Red card= 26/52
(26 are red)
a garden has more roses than daisies, and it has 9 daisies.furthermore, each flower in the garden has more then 3 petals.Let r represent the number of roses and let P represent the total number of petals in the garden. let’s compare the expressions P and 3(r+9). which statement is correct
Answer:
There is not enough info to tell
Step-by-step explanation:
Khan acadamey
Can someone do eight nine one and two ?
Answer: hello there here are your answers:
8) B multiplication property of zero
9) C additive identify
1) 8
2) -2a-7
Step-by-step explanation:
1) [tex]\frac{3+u}8^{2} \\u=5 \\so\\ \frac{3+5}8^{2} \\3+5=8^{2} \\8^{2} =\\64 \\\\ 64/8=\\\\\\8 \\there.\\\\\\[/tex]
2)[tex]-2(a-7)\\\\-2(a)(-7)\\\\=-2a+14\\\\\\there[/tex]
HELPPP PLEASEEE! I tried everything from adding to dividing, subtracting, multiplying but still no correct answer. Can someone help me out here please? I am not sure where to start either now. Thank you for your time.
You have some data points labeled by [tex]x[/tex]. They form the set {3, 5, 7}.
The mean, [tex]\bar x[/tex], is the average of these values:
[tex]\bar x = \dfrac{3+5+7}3 = \dfrac{15}3 = 5[/tex]
Then in the column labeled [tex]x-\bar x[/tex], what you're doing is computing the difference between each data point [tex]x[/tex] and the mean [tex]\bar x[/tex]:
[tex]x=3 \implies x-\bar x = 3 - 5 = -2[/tex]
[tex]x=5 \implies x-\bar x = 5-5 = 0[/tex]
[tex]x=7 \implies x-\bar x = 7 - 5 = 2[/tex]
These are sometimes called "residuals".
In the next column, you square these values:
[tex]x=3 \implies (x-\bar x)^2 = (-2)^2 = 4[/tex]
[tex]x=5 \implies (x-\bar x)^2 = 0^2 = 0[/tex]
[tex]x=7 \implies (x-\bar x)^2 = 2^2 = 4[/tex]
and the variance of the data is the sum of these so-called "squared residuals".
What’s is the domain
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Answer:
(b) x -3 ≥ 0
Step-by-step explanation:
The square root function will return non-negative values, so the inequality √(x-3) ≥ 0 gives no new information. What is required is that the argument of the square root function be non-negative:
x -3 ≥ 0
please solve both i have been struggling
Answer:
3
Step-by-step explanation:
make a column of x ,f, fx
then write income in x and no.of workers in f
andthen multiply both just like 100*3 ,100*2, 300*p, 400*2,500*1 write its answer fx
add the all fx and use this formula
mean =fx /n
260=adding total of fx divide by 5
Repeat same formula in no 2
HELP PLEASE!!!!!!!!!!!!!!!
Explanation:
The coefficients -24 and 8 divide to -24/8 = -3. Based on this alone, the answer is between choices B and C.
The m terms divide to [tex]\frac{m^5}{m^{-7}} = m^{5-(-7)} = m^{5+7} = m^{12}[/tex]
Notice how I subtracted the exponents. The general rule is [tex]\frac{a^b}{a^{c}} = a^{b-c}[/tex]
Since we get m^12, this points us to choice C as the final answer
For the sake of completeness, here's what the n terms divide to
[tex]\frac{n^4}{n^{-2}} = n^{4-(-2)} = n^{4+2} = n^{6}[/tex]
Jerry leaves home driving at 50 miles per hour. Ten minutes later, Jenny drives after him at the speed 65 miles per hour. When will she overtake him?
Hi there!
[tex]\large\boxed{\approx 43.33 min}}[/tex]
Recall:
d = st, where:
d = distance
s = speed
t = time
We can set up an expression where the extra ten minutes is taken into account:
50x = 65(x - 10) <--- because J left 10 minutes after, we must subtract from the time variable, or "x".
Solve for x:
50x = 65x - 650
Subtract 65x from both sides:
-15x = -650
Divide both sides by -15:
x ≈ 130/3 or 43.33 min
..................................................................
Answer:
Hello?
Step-by-step explanation:
