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Question
Marks obtained (in mathematics) by 9 students are given below:
60, 67, 52, 76, 50, 51, 74, 45 and 56
- Find the arithmetic mean.
- If marks of each student be increased by 4; what will be the new value of arithmetic mean?
Solution
a. Here, n = 9,
`barx = (x_1 + x_2 + ...... + x_n)/n`
∴ `barx = (60 + 67 + 52 + 76 + 50 + 51 + 74 + 45 + 56)/9`
= `531/9`
= 59
b. If marks of each student be incresed by 4 then new arithmetic mean will be = 59 + 4 = 63
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