Imagine that a researcher wanted to know the average weight

Imagine that a researcher wanted to know the average weight of 5th grade boys in a high school. He randomly sampled 5 boys from that high school. Their weights were: 120 lbs., 99 lbs, 101 lbs, 87 lbs, 140 lbs. The researcher posed a null hypothesis that the average weight for boys in that high school should be 100 lbs. What is the absolute value of calculated t that we use for testing the null hypothesis? (show work)

Solution

Formulating the null and alternative hypotheses,              
              
Ho:   u   =   100  
Ha:    u   =/   100  
              
              
Getting the test statistic, as              
              
X = sample mean =    109.4          
uo = hypothesized mean =    100          
n = sample size =    5          
s = standard deviation =    20.79182532          
              
Thus, t = (X - uo) * sqrt(n) / s =    1.010928029   [ANSWER]