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3 years ago

Shay and Nadine solve this problem in two different ways.

Mathematics

1 answer:

dezoksy [38]3 years ago

4 0

Answer:

20hrs

Step-by-step explanation:

165-25 = 140

140/7 = 20

= 20hrs.

This is because 20 x $7 = $140 +$25 in account = $165

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Division sentence 100mL into 10equal parts how many mL should we pour in each cup

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100/10 to find out how many mL to pour in each cup, equally
Which is 10

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4 years ago

6.200,6.532,6.6,6.4

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From lea st to greatest it would be 6.200, 6.4, 6.532, and 6.6

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3 years ago

Read 2 more answers

How large a sample should be selected to provide a 95% confidence interval with a margin of error of 6? Assume that the populati

marshall27 [118]

Using the z-distribution, it is found that a sample of 171 should be selected.

<h3>What is a z-distribution confidence interval?</h3>

The confidence interval is:

$\overline{x} \pm z\frac{\sigma}{\sqrt{n}}$

The margin of error is:

$M = z\frac{\sigma}{\sqrt{n}}$

In which:

$\overline{x}$ is the sample mean.

z is the critical value.

n is the sample size.

$\sigma$ is the standard deviation for the population.

For this problem, the parameters are:

$z = 1.96, \sigma = 40, M = 6$

Hence we solve for n to find the needed sample size.

$M = z\frac{\sigma}{\sqrt{n}}$

$6 = 1.96\frac{40}{\sqrt{n}}$

$6\sqrt{n} = 40 \times 1.96$

$\sqrt{n} = \frac{40 \times 1.96}{6}$

$(\sqrt{n})^2 = \left(\frac{40 \times 1.96}{6}\right)^2$

n = 170.7.

Rounding up, a sample of 171 should be selected.

More can be learned about the z-distribution at brainly.com/question/25890103

#SPJ1

4 0

2 years ago

The quality assurance engineer of a receiving-sets manufacturer inspects receiving-sets in lots of 50. He selects 4 of the 50 re

Mariana [72]

Answer:

0.0430 = 4.30% probability that exactly 2 of the 4 receiving-sets selected by the engineer are defective.

Step-by-step explanation:

Sets are chosen from the sample without replacement, which means that the hypergeometric distribution is used to solve this question.

Hypergeometric distribution:

The probability of x successes is given by the following formula:

$P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}$

In which:

x is the number of successes.

N is the size of the population.

n is the size of the sample.

k is the total number of desired outcomes.

Combinations formula:

$C_{n,x}$ is the number of different combinations of x objects from a set of n elements, given by the following formula.

$C_{n,x} = \frac{n!}{x!(n-x)!}$

In this question:

Lots of 50 means that $N = 50$

5 are defective, which means that $k = 5$

4 are selected, which means that $n = 4$

Find the probability that exactly 2 of the 4 receiving-sets selected by the engineer are defective.

This is $P(X = 2)$ . So

$P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}$

$P(X = 2) = h(2,50,4,5) = \frac{C_{5,2}*C_{45,2}}{C_{50,4}} = 0.0430$

0.0430 = 4.30% probability that exactly 2 of the 4 receiving-sets selected by the engineer are defective.

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3 years ago

Jared bought eighteen doughnuts to share with his coworkers. If each doughnut cost c cents, which expression represents his tota

Oduvanchick [21]

Wait, how many cents?

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2 years ago