JAMB - Mathematics (2009 - No. 41)
5, 8, 6 and k occur with frequency 3, 2, 4, and 1 respectively and have a mean of 5.7. Find the value of k?
4
3
2
1
Explicação
| x | f | fx | |
| 5 | 3 | 15 | |
| 8 | 2 | 16 | |
| 6 | 4 | 24 | |
| k | i | k | |
| ∑f=10 | ∑fx=55+k |
| Mean = | ∑fx |
| ∑fx |
| 5.7 = | 55+k |
| 10 |
57 = 55 + k
k = 57 - 55
k = 2