15 cattle can graze a field in 20 days, and 20 cattle can graze 3 such fields in how many days?
Q1. 15 cattle can graze a field in 20 days, and 20 cattle can graze 3 such fields in how many days?
Answer: 45 days
Explanation: 15 cattle graze 1 field in 20 days, so 3 fields require 900 cattle-days; 20 cattle take 900/20 = 45 days.