docabuzar
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
let, total work = LCM of 6,3,2
=6
Tom one hour work= \(\frac{6}{6}\) =1
Peter one hour work=\(\frac{6}{3}\) =2
John one hour work =\(\frac{6}{2}\) =3
Tom work of 1 hr = 1
Tom and Peter work for 1 hr = 1+2=3
now, the total amount of work left = 6-4=2
if all 3 work for an hour= 1+2+3=6
but we require 2 unit of work, so divide the whole by 3
total work in last t hour= \(\frac{1}{3}\)+\(\frac{2}{3}\)+\(\frac{3}{3}\) = 2
total work done by peter = 2+ \(\frac{2}{3}\)= \(\frac{8}{3}\)
the fraction of work done by peter=(8/3)/6= \(\frac{4}{9}\)
IMO is E