Question

You want to estimate the mean weight loss of people one year after using a popular weight loss program being advertised on TV. how many people on that program must be surveyed if we want to be 95% confident that the sample mean weight loss is within .25 lb of the true population mean? assume that the population standard deviation is known to be 10.6 lb.

6907
4865
84
6906

Answer 1

6907

Explanation:

reqired sample size is
`((t)/(b) )^(2) s^(2)`

where,

crititical value (t) = 1.96 for 95% conf.

margin of error (b) = 0.25

standard deviation (s) = 10.6

Za/2 = Z0.025 = 1.96

n ≥
`((1.96)/(0.25) )^(2) 10.6^(2)`

n >= 6906.27

n = 6907

In the question above, the given statement represent the answer as (6907).