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2 years ago

. Kenton completed 30% of a 90-page reading assignment. How many pages did he read?

Mathematics

2 answers:

JulijaS [17]2 years ago

6 0

Answer:

the pages that kenton read is B. 27 because to find the answer you need to divide first the percent that kenton completed which is 30% by 100 getting an decimal of 0.3. Finally you just multiply 0.3 times 90 which is all the pages and you get 27 so hopefully that is the correct answer.

Step-by-step explanation: :DDDDDDD and give me brainliest if you want and tell me if i got it right or not

spayn [35]2 years ago

3 0

Answer:

Step-by-step explanation:

hope it helps byeeeeeeeee

You might be interested in

Suppose that 5 J of work is needed to stretch a spring from its natural length of 30 cm to a length of 39 cm.

vesna_86 [32]

Answer

given,

work = 5 J

spring stretch form 30 cm to 39 cm

$W = \dfrac{1}{2}kx^2$

x = 0.39 - 0.30 = 0.09 m

$5 = \dfrac{1}{2}k\times 0.09^2$

$k = \dfrac{5\times 2}{0.09^2}$

k = 1234.568 N/m

a) work when spring is stretched from 32 cm to 34 cm

x₂= 0.34 -0.30 = 0.04 m

x₁ = 0.32 - 0.30 = 0.02

$W = \dfrac{1}{2}k(x_2^2-x_1^2)^2$

$W = \dfrac{1}{2}\times 1234.568 \times (0.04^2-0.02^2)^2$

W = 0.741 J

b) F = k x

25 = 1234.568 × x

x = 0.0205 m

x = 2.05 cm

3 0

4 years ago

The CPA Practice Advisor reports that the mean preparation fee for 2017 federal income tax returns was $273. Use this price as t

skad [1K]

Answer:

a) 0.6212 = 62.12% probability that the mean price for a sample of 30 federal income tax returns is within $16 of the population mean.

b) 0.7416 = 74.16% probability that the mean price for a sample of 50 federal income tax returns is within $16 of the population mean.

c) 0.8804 = 88.04% probability that the mean price for a sample of 100 federal income tax returns is within $16 of the population mean.

d) None of them ensure, that one which comes closer is a sample size of 100 in option c), to guarantee, we need to keep increasing the sample size.

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 $\mu$ and standard deviation $\sigma$ , the z-score of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

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 $\mu$ and standard deviation $\sigma$ , the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$ .

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

The CPA Practice Advisor reports that the mean preparation fee for 2017 federal income tax returns was $273. Use this price as the population mean and assume the population standard deviation of preparation fees is $100.

This means that $\mu = 273, \sigma = 100$

A) What is the probability that the mean price for a sample of 30 federal income tax returns is within $16 of the population mean?

Sample of 30 means that $n = 30, s = \frac{100}{\sqrt{30}}$

The probability is the p-value of Z when X = 273 + 16 = 289 subtracted by the p-value of Z when X = 273 - 16 = 257. So

X = 289

$Z = \frac{X - \mu}{\sigma}$

By the Central Limit Theorem

$Z = \frac{X - \mu}{s}$

$Z = \frac{289 - 273}{\frac{100}{\sqrt{30}}}$

$Z = 0.88$

$Z = 0.88$ has a p-value of 0.8106

X = 257

$Z = \frac{X - \mu}{s}$

$Z = \frac{257 - 273}{\frac{100}{\sqrt{30}}}$

$Z = -0.88$

$Z = -0.88$ has a p-value of 0.1894

0.8106 - 0.1894 = 0.6212

0.6212 = 62.12% probability that the mean price for a sample of 30 federal income tax returns is within $16 of the population mean.

B) What is the probability that the mean price for a sample of 50 federal income tax returns is within $16 of the population mean?

Sample of 30 means that $n = 50, s = \frac{100}{\sqrt{50}}$

X = 289

$Z = \frac{X - \mu}{\sigma}$

By the Central Limit Theorem

$Z = \frac{X - \mu}{s}$

$Z = \frac{289 - 273}{\frac{100}{\sqrt{50}}}$

$Z = 1.13$

$Z = 1.13$ has a p-value of 0.8708

X = 257

$Z = \frac{X - \mu}{s}$

$Z = \frac{257 - 273}{\frac{100}{\sqrt{50}}}$

$Z = -1.13$

$Z = -1.13$ has a p-value of 0.1292

0.8708 - 0.1292 = 0.7416

0.7416 = 74.16% probability that the mean price for a sample of 50 federal income tax returns is within $16 of the population mean.

C) What is the probability that the mean price for a sample of 100 federal income tax returns is within $16 of the population mean?

Sample of 30 means that $n = 100, s = \frac{100}{\sqrt{100}}$

X = 289

$Z = \frac{X - \mu}{\sigma}$

By the Central Limit Theorem

$Z = \frac{X - \mu}{s}$

$Z = \frac{289 - 273}{\frac{100}{\sqrt{100}}}$

$Z = 1.6$

$Z = 1.6$ has a p-value of 0.9452

X = 257

$Z = \frac{X - \mu}{s}$

$Z = \frac{257 - 273}{\frac{100}{\sqrt{100}}}$

$Z = -1.6$

$Z = -1.6$ has a p-value of 0.0648

0.9452 - 0.0648 =

0.8804 = 88.04% probability that the mean price for a sample of 100 federal income tax returns is within $16 of the population mean.

D) Which, if any of the sample sizes in part (a), (b), and (c) would you recommend to ensure at least a .95 probability that the same mean is withing $16 of the population mean?

None of them ensure, that one which comes closer is a sample size of 100 in option c), to guarantee, we need to keep increasing the sample size.

6 0

3 years ago

Shirley wants to find the distance her unicycle moves on the sidewalk when the tire makes one complete revolution. If the diamet

Evgesh-ka [11]

Answer:

44 in

Step-by-step explanation:

The circumference of the tire will be the same as the distance the unicycle moves in one complete revolution.

Find the circumference with the formula C = $\pi$ d, where d is the diameter

Plug in the values:

C = $\pi$ (14)

C = approx. 44 in

6 0

3 years ago

A game show has a contestant pick one of five doors to reveal the prize the contestant wins. A photo of a new boat is behind one

kumpel [21]

Hi,

It is unlikely that the game show contestant will win the boat.

To be exact it is 20% chance that the game show contestant will win the boat.

XD

7 0

2 years ago

Jeff uses the expression 2(3b + 1) to determine how many books (b) he needs to order for his store. If b= 12, how many books sho

arlik [135]

Answer:

74 books

Step-by-step explanation:

2(3b+1)

2(3(12)+1

2(36+1)

2(37)

7 0

3 years ago

Read 2 more answers