QQuestion
The following observations are arranged in ascending order:
27, 31, 46, 52, x, x + 4, 71, 79, 85, 90
If the median is 64, then the value of x is:
(a) 60
(b) 61
(c) 62
(d) 66
The following observations are arranged in ascending order:
27, 31, 46, 52, x, x + 4, 71, 79, 85, 90
If the median is 64, then the value of x is:
(a) 60
(b) 61
(c) 62
(d) 66
(c) 62
Explanation:
Number of observations, n = 10.
Since n is even, the median is the mean of the 5th and 6th observations.
5th observation = x
6th observation = x + 4
Median = \frac{x+(x+4)}{2}
Given that the median is 64:
\frac{2x+4}{2} = 64
⇒ x + 2 = 64
⇒ x = 64 − 2
⇒ x = 62
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