Question
The average of ‘x’ numbers is 30. If 50% of the numbers
are decreased by 6 and the remaining numbers are increased by 8, then find the new average of the ‘x’ numbers.Solution
ATQ,
Sum of ‘x’ numbers = 30x
New sum of the ‘x’ numbers = 30x – 0.5x × 6 + 0.5x × 8 = 31x
Therefore, new average = 31x/x = 31
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