A seven digit telephone number is of the form ABC-DEFG. In one particular state, the

A medical researcher wondered if there is a significant difference between the mean birth weight of boy and girl babies. Random

Yuliya22 [10]

Answer:

b) independent samples t-test

$t=\frac{(5.92 -5.74)-(0)}{\sqrt{\frac{1.88^2}{5}}+\frac{1.81^2}{5}}=0.154$

$p_v =2*P(t_{8}>0.154) =0.881$

So with the p value obtained and using the significance level given $\alpha=0.05$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the mean of the group 1 (boys) is NOT significantly different than the mean for the group 2 (Girls).

Step-by-step explanation:

The system of hypothesis on this case are:

Null hypothesis: $\mu_1 = \mu_2$

Alternative hypothesis: $\mu_1 \neq \mu_2$

Or equivalently:

Null hypothesis: $\mu_1 - \mu_2 = 0$

Alternative hypothesis: $\mu_1 -\mu_2\neq 0$

Our notation on this case :

$n_1 =5$ represent the sample size for group 1

$n_2 =5$ represent the sample size for group 2

We can calculate the mean and deviation for eaach group with the following formulas:

$\bar X= \frac{\sum_{i=1}^n X_i}{n}$

$s = \sqrt{\frac{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}}$

$\bar X_1 =5.92$ represent the sample mean for the group 1

$\bar X_2 =5.74$ represent the sample mean for the group 2

$s_1=1.88$ represent the sample standard deviation for group 1

$s_2=1.81$ represent the sample standard deviation for group 2

If we see the alternative hypothesis we see that we are conducting a bilateral test and with independnet samples t test.

b) independent samples t-test

The statistic is given by this formula:

$t=\frac{(\bar X_1 -\bar X_2)-(\mu_{1}-\mu_2)}{\sqrt{\frac{s^2_1}{n_1}}+\frac{S^2_2}{n_2}}$

And now we can calculate the statistic:

$t=\frac{(5.92 -5.74)-(0)}{\sqrt{\frac{1.88^2}{5}}+\frac{1.81^2}{5}}=0.154$

The degrees of freedom are given by:

$df=5+5-2=8$

And now we can calculate the p value using the altenative hypothesis:

$p_v =2*P(t_{8}>0.154) =0.881$

So with the p value obtained and using the significance level given $\alpha=0.05$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the mean of the group 1 (boys) is NOT significantly different than the mean for the group 2 (Girls).

7 0

3 years ago

It takes 12 hours for a single hose to fill a large vat. When a second hose is added, the vat can be filled in 4 hours. How many

aksik [14]

<h3>Answer:</h3>

6 hours

<h3>Step-by-step explanation:</h3>

The two hoses together take 1/3 the time (4/12 = 1/3), so the two hoses together are equivalent to 3 of the first hose.

That is, the second hose is equivalent to 2 of the first hose. Two of the first hose could fill the vat in half the time one of them can, so 6 hours.

The second hose alone can fill the vat in 6 hours.

_____

The first hose's rate of doing work is ...

... (1 vat)/(12 hours) = (1/12) vat/hour

If h is the second hose's rate of doing work, then working together their rate is ...

... (1/12 vat/hour) + h = (1/4 vat/hour)

... h = (1/4 - 1/12) vat/hour = (3/12 -1/12) vat/hour = 2/12 vat/hour

... h = 1/6 vat/hour

so will take 6 hours to fill 1 vat.

8 0

3 years ago

How do I write 3/4 and 1/6 as a complex fraction PLEASE HELP ITS DUE IN 12 mins!!

djverab [1.8K]

Answer:

3/4 as a complex fraction is -1^7/8(fraction form) and 1/6 as a complex fraction is -5/12 as a fraction

Step-by-step explanation:

6 0

2 years ago

Read 2 more answers

Find the product 3 • ( -7 )

Vera_Pavlovna [14]

Answer:-21

Step-by-step explanation:

3•(-7)

3 x -7=-21

4 0

3 years ago

JELP HURRY !!!!!!!!!

Tems11 [23]

You should be able to set up a proportion between the sides something like (18+x)/x=(56+21)/56

5 0

2 years ago