Answer
a. $H_0$: µ = 24.6 years, $H_1$: µ $\ne$ 24.6 years
The null hypothesis specifies that the average age of community college students remain unchanged which is 24.6 years., and the alternative hypothesis states that it will be different. The test is a two-tailed test, since the possible average age of community college students could be less than or more than 24.6 years.
b. $H_0$: µ = 51,497 dollars , $H_1$: µ $\ne$ 51,497 dollars
The null hypothesis specifies that the average income of accountant remain unchanged which is 51,497 dollars., and the alternative hypothesis states that it will be different. The test is a two-tailed test, since the possible average income of accountant could be less than or more than 51,497 dollars.
c. $H_0$: µ = 25.4 years , $H_1$: µ > 25.4 years
The null hypothesis is that the average age of attorneys equal to 25.4 dollars, and the alternative hypothesis states that the average age of attorneys is greater than 25.4 dollars. The test is a right-tailed test, since the interest is in the average age of attorneys that is greater than 25.4 years.
d. $H_0$: µ = score 88 , $H_1$: µ < score 88
The null hypothesis is that the average score of high school equals to 88, and the alternative hypothesis states that the average score of high school is less than 88. The test is a left-tailed test, since the interest is in the average age of attorneys that is less than 88.
e. $H_0$: µ = 70 beats , $H_1$: µ < 70 beats
The null hypothesis is that the average resting pulse rate of male marathon runners equals to 70 beats per minute, and the alternative hypothesis states that the average resting pulse rate of male marathon runners is less than 70 beats per minute. The test is a left-tailed test, since the interest is in the average resting pulse rate of male marathon runners is less than 70 beats per minute.
