Sakshi can finish a job in 20 days. Tanya is 25% more efficient than Sakshi. In how many days can Tanya finish the same job?

Problem restatementGiven Tanya is 25% more efficient (faster) than Sakshi, compute Tanya's time from Sakshi's time.

Given data

• Sakshi's time = 20 days → rate S = 1/20 job/day.
• Tanya's efficiency = 1.25 × S → rate T = 1.25 × (1/20) = 1/16 job/day.

Concept/ApproachTime is inverse of rate. If efficiency increases by 25%, time multiplies by 1/1.25.

Step-by-step calculation Tanya's time = 20 ÷ 1.25 = 16 days

VerificationDirect inverse check: rate 1/16 indeed corresponds to 16 days.

Common pitfalls

• Adding 25% to time (incorrect). The 25% applies to rate, not time.

Final Answer16 days