If the mean of the following frequency distribution is 8, find the value of p.
X | 3 | 5 | 7 | 9 | 11 | 13 |
F | 6 | 8 | 15 | P | 8 | 4 |
Let’s draw the table and calculate the relative value of variables ∑xi×fi
(xi) | (fi) | (xi×fi) |
3 | 6 | 18 |
5 | 8 | 40 |
7 | 15 | 105 |
9 | P | 9P |
11 | 8 | 88 |
13 | 4 | 52 |
∑fi = 41 + P | ∑xi×fi = 303 + 9P |
By putting the formula of mean we get;
Mean = (given)
So we have,
303 + 9P = 8 (41 + P)
303 + 9P = 328 + 8P
9P-8P = 328-303
P = 25
Hence the value of the P is 25.