A man’s working hours per day were increased by 25% and his wages per hour were increased by 20%. By how much percent were his daily earnings increased?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. 50%.
Let the number of working hours be x
Let the wages per hour be y
Initial daily earnings = Number of working hours × Wages per hour = xy
New number of working hours = x + (25/100) × x = 1.25x
New wages per hour = y + (20/100) × y = 1.2y
New daily earnings = Number of working hours x Wages per hour = (1.25x) × (1.2y) = 1.5xy
% Change in daily earnings = (Change in daily earnings)/(Initial daily earnings) × 100
%Increase in daily earnings = (1.5xy - xy)/xy × 100 = 50%