When birth weights were recorded for a simple random sample of

12

male babies born to mothers in a region taking a special vitamin supplement, the sample had a mean of

3.677

kilograms and a standard deviation of

0.656

kilogram. Use a 0.05 significance level to test the claim that the mean birth weight for all male babies of mothers given vitamins is different from

3.42

kilograms, which is the mean for the population of all males in this particular region. Based on these results, does the vitamin supplement appear to have an effect on birth weight?

t=