Question

Two men can do a piece of work in 6 hour and 4 respectively.After the first person had worked for 2 hour he is joined by the other By when should the work be completed?​

Answer 1

. let the two persons be a and b . a does work for 2 hours

. so part of the work completed be a=2/6=1/3

. in one hour a and b can do=1/6+1/4=(2+3)/12=5/12

. the remaining (1-1)/3=2/3work be completed =(2/3) 5/12)=2/3×12/5

=1.6 hours

the remaining work will be completed by both in 1.6

= 1hour and 36 minutes