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Let M denote the median of the following frequency distribution [figure] Then 20M is equal to :
(3) 208
[figure]
N=36 N2=18 ⇒ median class 8-12 (first c.f. 18)
l=8, C=12, f=10, h=4
M=l+ N2-Cf h=8+ 18-1210 4=10.4
20M=208
Answer: (3)
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