What is the value of the expression MATH HELP

We conclude that we fail to reject $H_0$ as there is not sufficient evidence to warrant support of the claim that less than 10 percent of the test results are wrong.

Step-by-step explanation:

We are given that among 317 tested subjects, results from 25 subjects were wrong.

We have to test the claim that less than 10 percent of the test results are wrong.

Let p = proportion of subjects that were wrong.

So, Null Hypothesis, $H_0$ : p = 10% {means that 10 percent of the test results are wrong}

Alternate Hypothesis, $H_A$ : p < 10% {means that less than 10 percent of the test results are wrong}

The test statistics that would be used here One-sample z proportion statistics;

T.S. = $\frac{\hat p-p}{\sqrt{\frac{\hat p (1-\hat p)}{n} } }$ ~ N(0,1)

where, $\hat p$ = sample proportion of test results that were wrong = $\frac{25}{317}$ = 0.08

n = sample of tested subjects = 317

So, test statistics = $\frac{0.08-0.10}{\sqrt{\frac{0.08 (1-0.08)}{317} } }$

= -1.31

The value of z test statistics is -1.31.

Now, the P-value of the test statistics is given by the following formula;

P-value = P(Z < -1.31) = 1 - P(Z $\leq$ 1.31)

= 1 - 0.9049 = 0.095

Now, at 0.05 significance level the z table gives critical value of -1.645 for left-tailed test. Since our test statistics is more than the critical value of z as -1.31 > -1.645, so we have insufficient evidence to reject our null hypothesis as it will not fall in the rejection region due to which we fail to reject our null hypothesis.

Therefore, we conclude that we fail to reject $H_0$ as there is not sufficient evidence to warrant support of the claim that less than 10 percent of the test results are wrong.

5 0

3 years ago

Sam runs a lemonade stand. One day he collected $6.55 in nickels and dimes. The number of nickels was 6 more than half the numbe

vampirchik [111]

Answer:

Total number of dimes collected = 50

Step-by-step explanation:

Let the number of dimes collected = d

And the number of nickels collected = n

On day collection in nickels and dimes = $6.55

Since, 1 nickel = $0.05

Therefore, 'n' nickels = 0.05n

And 1 dimes = $0.10

Value of 'd' dimes = $0.10d

Total value of 'n' nickels and 'd' dimes = $(0.05n + 0.10d)

So the equation for the total value will be,

0.05n + 0.10d = 6.55

5n + 10d = 655 --------(1)

Number of nickels was 6 more than half the number of dimes.

n = $\frac{d}{2}$ + 6 ------(2)

By substituting the value 'n' from equation (2) to equation (1)

5( $\frac{d}{2}$ + 6) + 10d = 655

$\frac{5d}{2}$ + 30 + 10d = 655

$\frac{25d}{2}$ = 655 - 30

25d = 625 × 2

d = $\frac{1250}{25}$

d = 50

Therefore, total number of dimes collected = 50

6 0

3 years ago