Aptitude - Time and Work - Discussion

Thank you very much rajendra.

@Baskar you have done great job. Just carry on.

@Bhaskar your explanation was superb. Carry on dude.

A = (1/20) * (80/100) = 1/25
1/A + 1/B =1/3(20/100)
1/B=(1/15) - (1/25) =2/75

A does 80% of work in 20 days which means he does 4% of work in a day (80/20 =4).

A and b does the remaining 20% work in 3 days which means in this 20 % of work A's contribution will be 4*3=12%.

Work done by b in 3 days = 20-12 = 8%.

Work done by b in 1 day = 8/3= 2.66.

Time taken by B to complete whole work= 100/2.66= 37.59.

We can't get exact answer but this will be time consuming.

A=80%
Remain 100 - 80 = 20%.

A = (1/20) * (80/100) = 1/25.
A+b = (1/3)+(20/100) = 1/15.
A+b.
(1/25) + b = 1/15.
B = 2/75,
B = 75/2,
B = 37(1/2).

A did only 80% of work out of total work in 20 days so
work done by A=80/100=5/4
so total workdone by A=20*5/4

How do we get that A & B together can do work in 15 days?

hey pls tell clearly ya its quite confusing

For all friends..
work = days

for A:
80% work = 20 days
4/5 work = 20 days
cross mul
1 work = 5/4 * 20 days
1 work = 25 days
A's 25 days = 1 work ----------------------------->1

A+B remain work done in 3 days
total work = 1
80% work = 4/5
100% work = 1
100% - 80% = 1 - 4/5 = 1/5

for A+B:
work = days
1/5 work = 3 days
cross mul
1 work = 15 days
dat is

A+B's 15 days = 1 work --------------------------->2

now we know A's and A+B's work
now find B's work
apply A's in A+B's
A+B 1 Days= 1/15 works
A's 1 days = 1/25 works---->from 1..

1/25 + B = 1/15 works
B's days = 1/15 - 1/25 Works
B's days= 2/75 works
we have to calc works
cross mul
B's work = 75/2 days = 37 1/2 days