Question

Henry can paint a room in 5 hours and nick can do it in 2 hours. How long will it take Henry and nick to paint the room together?

Answer 1

1 3/7hours

Explanation:

If Henry can paint a room in 5 hours, then he must be able to paint 1/5 of the room in 1hour

If nick can do it in 2 hours, he must be able to paint 1/2 of the room in 1 hour

Together they can paint (1/5+1/2) of the room in 1 hour

1/5+1/2 = (2+5)/10

= 7/10

This means that they can both paint 7/10 of the room in 1hour

Hence the can use 10/7 hours to paint 1room

Time taken for them to paint the room together is 10/7 hrs = 1 3/7hr