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SSC CHSL 2022 PYQ — Question 69

SSC CHSL - 31 May 2022 - Shift 3 • Quantitative Aptitude • Q69

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The score in maths of 50 students of a class is given in the following table. Calculate the mean score.

Interval Frequencies
0-10 2
10-20 11
20-30 28
30-40 6
40-50 3

 

Show answer & explanation

Correct answer: C

Explanation

The correct answer is option 3 i.e. 24.4

Formula Used:

Mean = ∑f(x)∑f\sum {f(x)} \over \sum{f}

Explanation:

According to the given table,

Interval Frequencies       x         f(x)  
0-10 2 5 10
10-20 11 15  165 
20-30 28 25 700
30-40 6 35 210
40-50 3 45 135

Now ∑f=50\sum f = 50 and ∑f(x)=1220\sum f(x) = 1220

So, mean = 1220501220 \over 50 = 24.4

HEnce the required answer is 24.4.