1. A movie was rated "unsuitable for under 15". The table shows the age distribution of those who attended one Saturday. What is the age and standard deviation of the distribution.
|
AGE |
15-19 |
20-24 |
25-29 |
30-34 |
35-39 |
40-44 |
45-49 |
|
FREQ |
8 |
10 |
16 |
26 |
22 |
12 |
6 |
| CLASS | x | d=x-A | f | fd | d2 | fd2 |
| 15-19 | 17 | -15 | 8 | 225 | ||
| 20-24 | 22 | 10 | 1000 | |||
| 25-29 | 27 | -5 | 16 | 25 | ||
| 30-34 | 32 | 0 | 26 | 0 | 0 | |
| 35-39 | 37 | 5 | 22 | 550 | ||
| 40-44 | 42 | 10 | 12 | |||
| 45-49 | 47 | 6 | 1350 | |||
| fd= | fd2= |