Answer:
option (a) It will be closer to 30 than to 20
Step-by-step explanation:
Data provided in the question:
For sample 1:
n₁ = 10
variance, s₁² = 20
For sample 2:
n₂ = 15
variance, s₂² = 30
Now,
The pooled variance is calculated using the formula,

on substituting the given respective values, we get

or
= 26.0869
Hence,
the pooled variance will be closer to 30 than to 20
Therefore,
The correct answer is option (a) It will be closer to 30 than to 20
The test statistic z will be equal to -0.946 and it shows that there is no significant difference in the proportion of rehires between full time and part time.
Given sample sizes of 833 and 386 and result of samples 434 and 189.

Proportion of full time=434/833=0.52
Proportion of part time=189/386=0.49.
Difference in proportion =0.52-0.49
TTF- i∈ rho=0
TTF+i∈ rho≠0.
Mean of difference=0.03
Z=(X-μ)/σ
σ=
=0.0317
σ=0.0317
z=(0-0.03)/0.0317
=-0.03/0.0317
=-0.317
p value will be =0.1736.
Because p value is greater than 0.01 so we will accept the null hypothesis which shows that there is no significant difference in the proportions.
Hence there is no significant difference in the proportion of rehires between full time and part time.
Learn more about z test at brainly.com/question/14453510
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<span>One nickel is 0.077 inches thick. Thus, a stack of nickels that is 100 inches tall would be composed of 100 divided by 0.077 nickels. So, a stack of nickels 100 inches tall would need 1299 nickels.</span>