Work and Rate

[alltimeacheiver]

Hi Gmat Gins Pls help me with this problem


A, b, C working alone finish consturcting house in 4,6,12 Hrs resp. A starts alone and work 1 hr. He then joined by b and they work together for 1 Hr. Finally c joined then all together to work for rest of the work. They start working 9.00 am in the morning and at what time they finish?

a. 11.30
b 12.00 pm
c 11.40 am
d 11.10 am
e 11.20 am

[HSPA]

1st hour : work complete = 0.25 as A can do 1/4 work in 1hour
2nd hour : A did another 1/4 and B did 1/6 of work = 5/12

Remaining work : 1-(1/4+5/12) = 1/3

A, B, C together can complete 1/2 work in 1 hour so they can complete 1/3 in how much time? 2/3 hour

so total time is 2+2/3 hour = 11.40am

[Anurag@Gurome]

Hi Gmat Gins Pls help me with this problem


A, b, C working alone finish consturcting house in 4,6,12 Hrs resp. A starts alone and work 1 hr. He then joined by b and they work together for 1 Hr. Finally c joined then all together to work for rest of the work. They start working 9.00 am in the morning and at what time they finish?

a. 11.30
b 12.00 pm
c 11.40 am
d 11.10 am
e 11.20 am

You have posted the same question 2 times.