Question
The average of ‘x’ numbers is 20. If 65% of the numbers
are decreased by 2 and the remaining numbers are increased by 5, then find the new average of the ‘x’ numbers.Solution
ATQ,
Sum of ‘x’ numbers = 20x
New sum of the ‘x’ numbers = 20x – 0.65x × 2 + 0.35x × 5 = 20.55x
Therefore, new average = 20.55x/x = 20.55
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