SOLUTION: The data for the number of visitors at a book club has been organized in the frequency table. <pre> Number of visitors: 6, 7, 8, 9, 10, 11, 12, 13 Frequency: 2, 5, n,

Number of visitors: 6, 7, 8, 9, 10, 11, 12, 13
 Frequency:         2, 5, n, 4, 4,  2,  2,  2

That table means: 
that there were 2 days when 6 visitors came,
that there were 5 days when 7 visitors came,
that there were n days when 8 visitors came,
that there were 4 days when 9 visitors came,
that there were 4 days when 10 visitors came,
that there were 2 days when 11 visitors came,
that there were 2 days when 12 visitors came,
that there were 2 days when 13 visitors came.

Look carefully at the problem in your book again.
You'll see that you left out something that was
given.  That could have either been the number of
weeks, or the total, or the mean number of visitors.

Suppose the mean number of visitors per day was given as, 
say, 9. Then that would mean that








What were you given that you left out?  If it happened
to be that the mean number of visitors per day was 9,
then n=6.  Check carefully to see what was given that
you forgot to tell us about.

Edwin