From generation to generation, the mean age when smokers first start to smoke varies. However, the standard deviation of that

Question

From generation to generation, the mean age
when smokers first start to smoke varies.
However, the standard deviation of that age
remains constant of around 2.1 years. A survey of
40 smokers of this generation was done to see if
the mean starting age is at least 19. The sample
mean was 18.1 with a sample standard deviation
of 1.3. Do the data support the claim at the 5%
level?

Kunduz · Accepted Answer

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