Example 1:

Suppose the null hypothesis is rejected. State the conclusion based on the results of the test. Six years ago, 12.9% of registered births were to teenage mothers. A sociologist believes that the percentage has decreased since then.

Which of the following is the correct conclusion?

A. There is sufficient evidence to conclude that the percentage of teenage mothers has decreased.

B. There is not isnot sufficient evidence to conclude that the percentage of teenage mothers has decreased.

C. There is not isnot sufficient evidence to conclude that the percentage of teenage mothers has remained the same.

D. There is sufficient evidence to conclude that the percentage of teenage mothers has remained the same.

Example 2

State the conclusion based on the results of the test. According to the Federal Housing Finance Board, the mean price of a single-family home two years ago was $299,400. A real estate broker believes that because of the recent credit crunch, the mean price has decreased since then. The null hypothesis is rejected.

Choose the Correct Answer

A. There is not sufficient evidence to conclude that the mean price of a single-family home has decreased from its level two years ago of $299,400.

B. There is sufficient evidence to conclude that the mean price of a single-family home has increased from its level two years ago of $299,400.

C. There is sufficient evidence to conclude that the mean price of a single-family home has decreased from its level two years ago of $299,400.

D. There is not sufficient evidence to conclude that the mean price of a single-family home has increased from its level two years ago of $299,400.