A 1/15 wall / day
B 1/20 wall / day
together 1/15 + 1/20 = 7/60 wall/day
times 4 days = 28/60 = 7/15 wall
Bilawal can build a wall in 15 days and Bilal in 20 days. If the work on it together for 4 days , then the fraction of the work ?
1 answer