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A batsman's average over 16 innings is 36. To raise the average to 38 in the 17th innings, he must score:
A58
B64
C76
D70
Answer & Solution
Correct answer: D. 70
1. The runs so far total 16 x 36 = 576.
2. For an average of 38 over 17 innings, the new total must be 17 x 38 = 646.
3. The runs needed are the difference, 646 - 576.
4. So he must score 70.
5. A shortcut check: the new average is 2 more, and 16 earlier innings each need topping up by 2, so 38 + 32 = 70.
_Source: NCERT Class 10 Maths, Ch 13 'Statistics', S13.2 Mean of Grouped Data_
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