A company makes muesli which contains nuts and sultanas. They counted the number of nuts in 50 individual serving packets. They drew a table Number of nuts
4-6
7-9
10-12
13-15
16-18
Midpoint (x)
5
8
11
14
17
Number of packets (f)
3
9
12
17
9
50
fx
15
?
?
?
?
?
a) Complete the table
b) Calculate an estimate for the mean.