Question

The water diet requires one to drink two cups of water every half hour from when one gets up until one goes to bed, but otherwise allows one to eat whatever one likes. Four adult volunteers agree to test the diet. They are weighed prior to beginning the diet and after six weeks on the diet. The weights ( in pounds) are Person 1 2 3 4 Weight before diet 180 125 240 150 Weight after diet 170 130 215 152 For the population of all adults, assume that the weights loss after six weeks on the diet ( weight before beginning the diet---weight after six weeks on the diet) is Normally distributed with mean μ.

a. Test the hypothesis if the diet leads to weight loss

Answer 1

Computational Table:

Hypothesis:

or Weight before the diet > Weight after the diet OR diet leads to weight loss.

Where, D = (Weight before the diet - Weight after the diet)

Calculation:

Test statistic:

Degrees of Freedom = n-1 = 4-1 = 3

Critical value:

                 …………..Using t table

Conclusion:

t < Critical value, i.e 1.03 < 2.3534, That is Fail to Reject Ho at 5% level of significance

We would not reject Ho at 5% level of signficance.

Therefore, there is Not sufficient evidence to conclude that, the diet leads to weight loss.