Class interval
1 - 5
6 - 10
11 - 15
16 - 20
21 - 25
Frequency
6
15
20
7
2
Estimate the median of the frequency distribution above
A
10\(\frac{1}{2}\)
B
11\(\frac{1}{2}\)
C
12
D
13
Verified Correct Answer: C.
Step-by-Step Mathematical Solution
Median = L + [\(\frac{\frac{N}{2} - f}{fm}\)]h
N = Sum of frequencies
L = lower class boundary of median class
f = sum of all frequencies below L
fm = frequency of modal class and
h = class width of median class
Median = 11 + [\(\frac{\frac{50}{2} - 21}{20}\)]5
= 11 + (\(\frac{25 - 21}{20}\))5
= 11 + (\(\frac{(4)}{20}\))
11 + 1 = 12
Source: Myschool Past Questions Archive (Record #31122)