Question

Madhu and Shiney together can complete a piece of work in 20 days, Shiney and Rosy together can complete the same work in 12 days, and Rosy and Madhu together can complete the work in 15 days. In how many days will three of them complete it together?

• A. 12 days
• B. 5 days
• C. 15 days
• D. 10 days

Answer 1

Answer:

D. 10 days

Madhu and Shiney together can complete the work in =20 days

shiney and rosy can =12

rosy and madhu can =15

LCM of these days are the total work =60

efficiency of Madhu and Shiney=$60/20=3$

efficiency of shiney and rosy =$60/12=5$

efficiency of rosy and madhu =$60/15=4$

$2(madhu+shiney+rosy)=5+4+3=12$

together they can complete the work in $=(60/12)\times2=10days$