Q. A man completes 7/8 of a job in 21 days. How many more days will it take him to finish the job if quantum of work is further increased by 50%

Explanation : 

A man completes 7/8 of a job in 21 days ….

Given:
– Man completes 7/8 of work in 21 days
– Work increases by 50%

Step 1: Find Rate of Work
– Total work = W
– Rate = (7/8)W ÷ 21 = W/24 per day

Step 2: Calculate New Work
– Increased work = 1.5W
– Already completed = 7/8W
– Remaining = 1.5W – 7/8W = 5/8W

Step 3: Calculate Days Required
– Time = Remaining work ÷ Rate
– = (5/8W) ÷ (W/24)
– = 15 days

Answer: 15 additional days required