Answer :
Given that :
randomly selected customers = 25
mean of years = 33.68
standard deviation =10.57
sample size has been = 225
(A). now we need to find out degrees of freedom for the t-statistic
when n = 25
we know that the
the degree of freedom = n - 1
= 25 - 1
= 24
the degree of freedom for the t-statistic is 24
(B). now we need to find out degrees of freedom for the t-statistic
when n = 225
we know that the
the degree of freedom = n - 1
= 225 - 1
= 224
the degree of freedom for the t-statistic is 224
Please answer a and b years. a) How many degrees of freedom does the t-statistic have?...
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