The Raitio of 20:360

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

Click and drag like terms onto each other to simplify fully.<br> 2-5+7y-5x+7x-2y

nikdorinn [45]

Answer: 5y + 2x - 3

(In simplest form)

6 0

3 years ago

Read 2 more answers

How does the volume of a cylinder change when its diameter is tripled

cupoosta [38]

V(cylinder)= πr²h
d=2r,
d is diameter, r is radius.
When diameter is tripled, a new diameter D=3d,
new radius R=3d/2=(3*2r)/2=3r
R=3r

V(new cylinder)= πR²h = π(3r)²h=9πr²h

V(new cylinder)/V(cylinder)=9πr²h/πr²h=9

Volume new cylinder 9 times more the volume of old cylinder.

5 0

3 years ago

Read 2 more answers

What is the x for 1/2x=150

notsponge [240]

X=300. basically multiply 150 times 2 to get the number. To check if it’s right divided 300 by 2 and see if it’s 150 or not. If not Choose another number

6 0

2 years ago

Sarina throws a ball up into the air, and it falls on the ground nearby. The ball's height, in feet, is modeled by the function

tangare [24]

Answer:

(C) 3 feet

Step-by-step explanation:

We have a function of f(x) here. When Sarina throws the ball, it has been 0 seconds since she threw it.

Since x represents the amount of seconds, we can find the height of the ball (f(x)) by substituting x in as 0.

$-0^2 - 0 + 3$

0 squared is 0, 0 minus zero is 0, and 0+3 = 3, so

$f(x) = 3$

Meaning that when Sarina threw the ball, it's height was 3 feet.

Hope this helped!

7 0

3 years ago