Statisticshard · Past Paper
Find the missing frequency f for the class 20-30 if the median is 25, N=60, cf=20, and class interval size is 10.
A10
B20
C30
D40
✓ Correct Answer: B — 20
Median = L + [(N/2 - cf)/f]*i => 25 = 20 + [(30 - 20)/f]*10 => 5 = 100/f => f = 20.
Share this question
More from Statistics
- A die is thrown twice. What is the probability that 5 will come up at least once?
- If the mean of first $n$ odd natural numbers is $n^2/81$, find $n$.
- If the sum of squares of deviations from the mean is zero, then:
- If the sum of 50 observations is 2500, what is the mean?
- What is the arithmetic mean of the first five natural numbers?