Answer:
We conclude that young women are delaying marriage and marrying at a later age.
Step-by-step explanation:
We are given that the average age of brides marrying for the first time is 23.9 years with a population standard deviation of 4.2 years.
The sociologist randomly samples 100 marriage records and determines the average age of the first time brides is 24.9 years.
Let
= <u><em>average age of brides marrying for the first time.</em></u>
So, Null Hypothesis,
:
= 23.9 years {means that young women are not delaying marriage and marrying at a later age}
Alternate Hypothesis,
:
> 23.9 years {means that young women are delaying marriage and marrying at a later age}
The test statistics that would be used here <u>One-sample z test statistics</u> as we know about the population standard deviation;
T.S. =
~ N(0,1)
where,
= sample average age of the first time brides = 24.9 years
= population standard deviation = 4.2 years
n = sample of marriage records = 100
So, <u><em>the test statistics</em></u> = 
= 2.381
The value of z test statistics is 2.381.
<u>Now, at 1% significance level the z table gives critical value of and 2.326 for right-tailed test.</u>
Since our test statistic is more than the critical value of z as 2.381 > 2.326, so we have sufficient evidence to reject our null hypothesis as it will fall in the rejection region due to which <u>we reject our null hypothesis</u>.
Therefore, we conclude that young women are delaying marriage and marrying at a later age.