Question
A number is first increased by 25% and then decreased by
25%. If the net change in the number is 187.5, then find the original number.Solution
ATQ, Let the original number be '100a'. Final number = 100a x (125/100) x (75/100) = '93.75a' Net decrease = 100a - 93.75a = '6.25a' Or, 6.25a = 187.5 Or, 'a' = 187.5 / 6.25 = 30 Therefore, required number = 100a = 30 x 100 = 3000
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