Painting Trio

[intrepid17]

Word Translations Question Bank

Tom, working alone, can paint a room in 6 hours. Peter and John, working independently, can paint the same room in 3 hours and 2 hours, respectively. Tom starts painting the room and works on his own for one hour. He is then joined by Peter and they work together for an hour. Finally, John joins them and the three of them work together to finish the room, each one working at his respective rate. What fraction of the whole job was done by Peter?


a)1/9
b)1/6
c)1/3
d)7/18
e)4/9


Tom paints room alone for 1 hour and hence completes 1/6 th of total work.

Remaining work = 5/6 of total work

now Peter and tom work for 1 hour , so they complete 1/2 of remaining work = 5/6 * 1/2 of total work.

Doubt : Why does the explantion says that peter and Tom complete 1/2 of total original work ?

[thoppae.saravanan]

Tom can complete 1/6 of work in 1 hour.
Peter can complete 1/3 of work in 1 hour.

So the explanation states that tom and peter working together (1/6 + 1/3 = 1/2) will complete half of the remaining work in one hour.

[jnelson0612]

Good explanation thoppae. Thank you.