Question

Consider the gain in weight of 14 randomly selected female rats between 28 and 84 days after birth. Seven were fed on a high protein diet and

the other seven on a low protein diet. Known that weight gain under different diet follow normal distribution. Test, at the 10% level of

significance, whether the mean weight gain under high protein diet is greater than that under low protein diet.

Low protein   70    118 101    85 107    132    94

High protein    134    83 146    104 119    97    124

(a) [1] State the null and alternative hypotheses.

(b) [1] Calculate the test statistic.

(c) [1] Find the corresponding p-value.

(d) [1] Make the decision according to (c).

(e) [1] Give the conclusion by the decision made from (d).

Answer 1

Let us denote the difference

d = weight gain under low protein diet - weight gain under high protein diet

There is sufficient evidence to support the claim that the mean weight gain under high protein diet is greater than that under low protein diet..