Determine whether the statement is true or false. If it is true, explain why.

What percent of 70 is 10.5? (write your answer as a percent) A) 10.5% Eliminate B) 11.0% C) 12.5% D) 15.0%

Roman55 [17]

Answer:

Option D) 15%

Step-by-step explanation: 10.5/70= .15

.15x100=15

It would be easier to think it through if instead for 70 we took the number 100. Lets reword it and say what percent of 100 is 38? This would be easy to answer it would be 38% But how you check it is, you take 38 and divide by the total (100) which is .38 then multiply by 100 you will get 38% Same with your equation take the 10.5 and divide by the total amount which is 70 you will get .15 then multiply by 100. the answer will be 15%

7 0

4 years ago

Read 2 more answers

A survey collected data on annual credit card charges in seven different categories of expenditures: transportation, groceries,

Andru [333]

Answer:

A. Null and alternative hypothesis:

$H_0: \mu_d=0\\\\H_a:\mu_d\neq 0$

B. Yes. At a significance level of 0.05, there is enough evidence to support the claim that there is signficant difference between the population mean credit card charges for groceries and the population mean credit card charges for dining out.

P-value = 0.00002

C. As the difference is calculated as (population 1 − population 2), being population 1: groceries and population 2: dinning out, and knowing there is evidence that the true mean difference is positive, we can say that the groceries annual credit card charge is higher than dinning out annual credit card charge.

The point estimate is the sample mean difference d=$840.

The 95% confidence interval for the mean difference between the population means is (490, 1190).

Step-by-step explanation:

This is a hypothesis test for the population mean.

The claim is that there is signficant difference between the population mean credit card charges for groceries and the population mean credit card charges for dining out.

Then, the null and alternative hypothesis are:

$H_0: \mu_d=0\\\\H_a:\mu_d\neq 0$

The significance level is 0.05.

The sample has a size n=42.

The sample mean is M=840.

As the standard deviation of the population is not known, we estimate it with the sample standard deviation, that has a value of s=1123.

The estimated standard error of the mean is computed using the formula:

$s_M=\dfrac{s}{\sqrt{n}}=\dfrac{1123}{\sqrt{42}}=173.2827$

Then, we can calculate the t-statistic as:

$t=\dfrac{M-\mu}{s/\sqrt{n}}=\dfrac{840-0}{173.2827}=\dfrac{840}{173.2827}=4.848$

The degrees of freedom for this sample size are:

$df=n-1=42-1=41$

This test is a two-tailed test, with 41 degrees of freedom and t=4.848, so the P-value for this test is calculated as (using a t-table):

$\text{P-value}=2\cdot P(t>4.848)=0.00002$

As the P-value (0.00002) is smaller than the significance level (0.05), the effect is significant.

The null hypothesis is rejected.

At a significance level of 0.05, there is enough evidence to support the claim that there is signficant difference between the population mean credit card charges for groceries and the population mean credit card charges for dining out.

We have to calculate a 95% confidence interval for the mean difference.

The t-value for a 95% confidence interval and 41 degrees of freedom is t=2.02.

The margin of error (MOE) can be calculated as:

$MOE=t\cdot s_M=2.02 \cdot 173.283=350$

Then, the lower and upper bounds of the confidence interval are:

$LL=M-t \cdot s_M = 840-350=490\\\\UL=M+t \cdot s_M = 840+350=1190$

The 95% confidence interval for the mean difference is (490, 1190).

7 0

3 years ago

Simplify. 43 – 2 A 10 B 41 C 62 D 79

Zarrin [17]

the correct answer is, B.

41

8 0

3 years ago

B

nasty-shy [4]

Answer:

Step-by-step explanation:

{y2+8y−128=0x=34⋅(y+4) ... The two right triangle are similar, so: BDAB=DEAC. From this, I obtain: ... AC=3x AB=4x (3x)²+(4x)²=225 x=3 BD=8 AB/AC=BD/DE 12/9=8/DE DE=6.

8 0

4 years ago

Jose bought 9 movie tickets for a total of $54. Adult tickets cost $8 each and child tickets cost $3.50. How many adult tickets

MArishka [77]

Answer:

5

Step-by-step explanation:

5 x 8 = 40

3.50 x 4 = 14

4 0

3 years ago