Mathematics
Find the numerical value of x, if the mean of the following frequency distribution is 12.58.
| Variate | Frequency |
|---|---|
| 5 | 2 |
| 8 | 5 |
| 10 | 8 |
| 12 | 22 |
| x | 7 |
| 20 | 4 |
| 25 | 2 |
Measures of Central Tendency
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Answer
| Variate (x) | Frequency (f) | fx |
|---|---|---|
| 5 | 2 | 10 |
| 8 | 5 | 40 |
| 10 | 8 | 80 |
| 12 | 22 | 264 |
| x | 7 | 7x |
| 20 | 4 | 80 |
| 25 | 2 | 50 |
| Total | ∑ f = 50 | ∑fx = 524 + 7x |
We know that,
n = ∑f = 50.
By formula,
⇒ 12.58(50) = 524 + 7x
⇒ 629 = 524 + 7x
⇒ 7x = 629 - 524
⇒ 7x = 105
⇒ x =
⇒ x = 15.
Hence, numerical value of x is 15.
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