18. A recent article claimed that women are waiting longer to have their first

child. The article estimates that the average age of first-time mothers is 26 years

old, which is up from 21 years old in 1970. The margin of error for the estimate

was 1.5 years. Based on the estimate and the margin of error, which of the

following is an appropriate conclusion?

(A) 95% of the women in the study were 26 years old when they had their first child.

(B) The age of every first-time mother in the sample must have been between 24.5 and

27.5 years old.

(The age of every first-time mother in the sample must have been between 23 and

29 years old.

(D) This study proves that women are waiting longer to have their first child.

(E) It is plausible that the average age of first-time mothers is 27 years old.

Question

Mathematics

Royce Waters

21 April, 00:11

18. A recent article claimed that women are waiting longer to have their first

child. The article estimates that the average age of first-time mothers is 26 years

old, which is up from 21 years old in 1970. The margin of error for the estimate

was 1.5 years. Based on the estimate and the margin of error, which of the

following is an appropriate conclusion?

(A) 95% of the women in the study were 26 years old when they had their first child.

(B) The age of every first-time mother in the sample must have been between 24.5 and

27.5 years old.

(The age of every first-time mother in the sample must have been between 23 and

29 years old.

(D) This study proves that women are waiting longer to have their first child.

(E) It is plausible that the average age of first-time mothers is 27 years old.

+3

Answers (1)

Know the Answer?

Twix · Answer 1

Answer:E

Step-by-step explanation:

The margin of error of 1.5 years indicates that we are confident the population mean age is captured i. The interval 26-1.5=24.5 to 26+1.5=27.5 years old. Therefore, it is plausible that the average age of first time mothers is 27 years old.