SOLUTION: A random sample of 20 young men was taken. One half of the group was given coffee containing caffeine while the other half was given decaffeinated coffee as the placebo control.

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Question 1183991: A random sample of 20 young men was taken. One half of the group was given coffee
containing caffeine while the other half was given decaffeinated coffee as the placebo
control. The pulse rate was measured after the subjects have drunk their coffee. The results
were:
12 men were given placebo with a mean of 65 and variance of 31.11
8 men were given Caffein with a mean of 78 and variance of 28.67
Test the hypothesis that caffeine has no effect on the pulse rates of young men (use a 1%
level of significance).
Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website!
two sample t
Ho: mu1=mu2
Ha: NE
alpha=0.01 p{reject Ho|Ho true}
t=(65-78)/sqrt ((31.11/12)+(28.67)/8)
=-13/2.485
=-5.23
strongly reject Ho and there is an effect upon the pulse rates, p=0.0001