Question

3. A survey in a recent issue of Prevention magazine reported that 39% of physicians said that they took vitamin E supplements regularly. To test the claim, a researcher randomly selected 115 physicians and found 55 who said that they took vitamin E supplements. At a = .02 test the claim that 39% of the physicians took vitamin E supplements and find the P-value for the test.

Answer 1

Solution :-

Givan that ,

n = 115

x = 55

This is the two tailed test .

The null and alternative hypothesis is

H0 : p = 0.39

Ha : p 0.39

= x / n = 55 / 115 = 0.4783

P0 = 39% = 0.39

Test statistic = z

= - P0 / [P0 * (1 - P0 ) / n]

= 0.4783 - 0.39 / [0.39 ( 1- 0.39 ) / 115 ]

= 1.941

The test statistic = 1.941

The P-value = 0.0523