Question

Twenty men can finish a piece of work in 30 days. when should 5 men leave the work so that it may be finished in 35 days

Answer 1

☆heya your answer is here☆

rate of 1 man per day=1/(20*30)=1/600
let d=number of days with 20 workers
20d/600+[15(35-d)]/600=1
d=15 days