1. Which numerical expression has the value of 60?

Tia takes $50 from her bank account to pay for bus fare for the month. She does this each month for 7 months in a row. Which equ

olga55 [171]

Answer:

B. - $50 * 7 = - $350

Step-by-step explanation:

Taking $50 each month causes - $50 change to bank balance

<u>Repeating same for 7 month:</u>

- $50 * 7 = - $350

Correct option is B

6 0

2 years ago

Read 2 more answers

dataset a has a mean of 215 and a standard deviation of 35. Dataset B has a mean of 400 and a standard deviation of 12. Which da

GREYUIT [131]

I think it is Dataset B Does that help?

6 0

2 years ago

Read 2 more answers

Lionel computed the average rate of change in the depth of a pool over a two-week interval to be zero. Which statement must be t

gayaneshka [121]

Answer:The pool must have been the same depth at the start of the interval as it was at the end of the interval.

Step-by-step explanation:

The average rate of change is calculated as:

[final value - initial value] / time interval.

Then, the average rate of change does not take into account intermediates values, and you cannot draw any conclusion about such intermediate values.

In the given case you have:

average rate of change in depth = [final depth - initial depth] / 2 weeks.

0 = [final depth - initial depth] / 2 weeks.

⇒ 0 = final depth - initial depth

⇒ final depth = initial depth.

That is why the conclusion is the second statement of the answer choices: the pool must have been the same depth at the start of the interval as it was at the end of the interval.

In between the pool might have been deeper, more shallow, empty or change in any form, since the average rate of change does not tell the full history but only the net change.

4 0

2 years ago

According to government data, the probability that an adult was never in a museum is 10%. In a random survey of 60 adults, wh

lutik1710 [3]

Answer:

$\text{Mean}=)=6\\\\\text{Standard deviation}=2.324$

Step-by-step explanation:

Given : The probability that an adult was never in a museum is : p=0.10

The number of adults randomly surveyed: n = 60

In Binomial distribution , the formula to find the mean and the standard deviation is given by :-

$\text{Mean}=np\\\\\text{Standard deviation}=\sqrt{np(1-p)}$

Then , the mean and standard deviation of the number that were never in a museum will be :-

$\text{Mean}=60(0.10)=6\\\\\text{Standard deviation}=\sqrt{60(0.10)(1-0.1)}=2.3237900077\approx2.324$

5 0

2 years ago

Bones Brothers & Associates prepare individual tax returns. Over prior years, Bones Brothers have maintained careful records

madreJ [45]

Answer:

For this case we have the following info related to the time to prepare a return

$\mu =90 , \sigma =14$

And we select a sample size =49>30 and we are interested in determine the standard deviation for the sample mean. From the central limit theorem we know that the distribution for the sample mean $\bar X$ is given by:

$\bar X \sim N(\mu, \frac{\sigma}{\sqrt{n}})$

And the standard deviation would be:

$\sigma_{\bar X} =\frac{14}{\sqrt{49}}= 2$

And the best answer would be

b. 2 minutes

Step-by-step explanation:

Previous concepts

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The central limit theorem states that "if we have a population with mean μ and standard deviation σ and take sufficiently large random samples from the population with replacement, then the distribution of the sample means will be approximately normally distributed. This will hold true regardless of whether the source population is normal or skewed, provided the sample size is sufficiently large".

Solution to the problem

For this case we have the following info related to the time to prepare a return

$\mu =90 , \sigma =14$

And we select a sample size =49>30 and we are interested in determine the standard deviation for the sample mean. From the central limit theorem we know that the distribution for the sample mean $\bar X$ is given by:

$\bar X \sim N(\mu, \frac{\sigma}{\sqrt{n}})$

And the standard deviation would be:

$\sigma_{\bar X} =\frac{14}{\sqrt{49}}= 2$

And the best answer would be

b. 2 minutes

3 0

2 years ago