Question
The average of ‘x’ numbers is 25. If 70% of the numbers
are decreased by 3 and the remaining numbers are increased by 9, then find the new average of the ‘x’ numbers.Solution
ATQ,
Sum of ‘x’ numbers = 25x
New sum of the ‘x’ numbers = 25x – 0.7x × 3 + 0.3x × 9 = 25.4x
Therefore, new average = 25.4x/x = 25.4
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