Statisticshard · Past Paper
In a continuous series, the median is 35 and the median class is 30-40. If f=10 and h=10, and N=50, what is the 'cf' of the pre-median class?
A20
B25
C15
D10
✓ Correct Answer: A — 20
35 = 30 + [(25 - cf)/10]*10 $\Rightarrow$ 35 = 30 + 25 - cf $\Rightarrow$ cf = 20.
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