Use the following information for questions:
A researcher wants to assess if the average age when women first marry has increased from 1960 to 1990. Let $µ_1$ = average age of first marriage for women in 1990 and $µ_2$ = average age of first marriage for women in 1960. A random sample of 10 women married in 1990 showed an average age at marriage of 24.95 years, with a sample standard deviation of 2 years. A random sample of 20 women married in 1960 showed an average age at marriage of 23.1 years, with a sample standard deviation of 1.5 years. Assume that age of first marriage for women is normally distributed, but do not assume the population variances are equal. Use the conservative "by hand" estimate for the degrees of freedom.
-Which of the following is an appropriate conclusion?
A) The average age of first marriage for women in 1990 does appear to be greater than the average age in 1960.
B) The results are not statistically significant so there is not enough evidence to conclude that the average age in 1990 is greater than the average age in 1960.
C) The average age of marriage is at least 23 years old for both 1960 and 1990.
D) None of the above.

Question

Use the following information for questions:
 A researcher wants to assess if the average age when women first marry has increased from 1960 to 1990. Let $µ_1$ = average age of first marriage for women in 1990 and $µ_2$ = average age of first marriage for women in 1960. A random sample of 10 women married in 1990 showed an average age at marriage of 24.95 years, with a sample standard deviation of 2 years. A random sample of 20 women married in 1960 showed an average age at marriage of 23.1 years, with a sample standard deviation of 1.5 years. Assume that age of first marriage for women is normally distributed, but do not assume the population variances are equal. Use the conservative "by hand" estimate for the degrees of freedom.
-Which of the following is an appropriate conclusion?
A) The average age of first marriage for women in 1990 does appear to be greater than the average age in 1960.
B) The results are not statistically significant so there is not enough evidence to conclude that the average age in 1990 is greater than the average age in 1960.
C) The average age of marriage is at least 23 years old for both 1960 and 1990.
D) None of the above.

Quizplus · Accepted Answer

Given the sample data, the average age of first marriage for women in 1990 is higher than in 1960, suggesting an increase in the average age at first marriage over the 30-year period. This conclusion is based on the sample means provided (24.95 years in 1990 vs. 23.1 years in 1960) and does not require statistical testing to observe the apparent difference.

Use the Following Information for Questions: a Researcher Wants µ1µ_1µ1​

Use the Following Information for Questions:
a Researcher Wants $µ_1$