Aptitude - Time and Work - Discussion

How you got 6/60?

I think the answer is 12.

How it is user
Now, 1 work is done in 3 days.
5
Whole work will be done in (3 x 5) = 15 days.

@Vishnu...

As per the statement A will do the work three days continuosly but only on third day B & C will assist, so
A's thrid day work must also include with both B & C
that's why...
(A + B + C)'s 1 day's work is taken

1/20+1/(30X3)+1/(60X3) = 1/15
Is my way of solving correct?

There's a simple logic friends,

If a person wrks for n days, his 1 day's work is 1/n.
or the other way round,
if 1/n is the 1 day's work then he works for n days.
& it can be very well known if 1 day's work is known it can be multiplied with any numbers of days you wish to.

Similarely,

Here last statement tell the same i.e. 3days work is 1/5,
so to calculate 1 day's work we need to divide it by 3 wiz gives 1/15.
so if 1/15 is 1 day's work then they together work for 15 days.
& the logic behind 2 days & 3 dats work is :
A's 2 days work is (1/20)*2, i.e 1 day's multiplied by nth day.

but on the "3rd day" they all A,B&C work together wiz equals to 1/10.

Therefore 2 days + 3rd day's wrk gives 3 day's work.

Why we take 2 days? Please help.

@vikas.

Superb explanation. :-).

@chitra
assisted by B and C on every third day
it means A's 2 days + (B&C)'s 1 day
from d 1st explanation u got
Work done in 3 days=(1/10 + 1/10)=1/5
dat is in 3 days=1/5 works
in ques dey ask "In how many days can A do the work"
now cross multiply..
(5*3) days=1 work..
1 work = 15 days...
now u got it ah?

Nice explanation baskar.

Thank you Vikas for your information, I have understood.