Question
A student scored an average of 81 marks in his first 30
tests. In the next 10 tests, his average score was ‘x’ marks, and his overall average rose to 84 marks. Find the value of 'x'.Solution
ATQ,
{81 × 30 + 10 × x}/(30 + 10) = 84
Or, 10x + 2430 = 84 × 40 = 3360
Or, 10x = 930
Or, x = 93
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