CAT Question Bank - Time & Work
Ishita last edited by
@rowdy-rathore could u plzz explain bcz mine is 20
zabeer last edited by zabeer
@Ishita 22.5 is the right answer.
A does 3x and B does x amount of work in a given amount of time.
as work is inversely proportional to the time taken, A takes t days and B takes 3t days to complete a given amount of work.
we know 3t - t = 60 days
t = 30 days
So A takes 30 days and B takes 30 + 60 = 90 days
Together, 1/30 + 1/90 = 4/90 of work will be completed and it will take 90/4 = 22.5 days to finish the work together.
zabeer last edited by
@Ishita 120 is correct. Can you share your detailed approach so that others will benefit :)
@Rowdy-Rathore answer/explaination ??
Tanuj79 last edited by
@rowdy-rathore, at first they ran at full capacities for 3 minutes, then they ran at reduced capacities for 1 minute. Hence, they started again after 4 minutes.
after calculating we got 12x-660
we can equate this with 8x.
by equating 1 and 2
using equation 3
@rowdy-rathore x takes 43=12 days to complete the job=> work done in 1 day=1/12
y takes36=18 days to complete the job=> work done in 1 day=1/18
z takes 52=10 days to complete the job=> work done in 1 day=1/10
Work done by all of them in 3 days=3(1/12+1/18+1/10)
if y takes a days,
@rowdy-rathore 15 days a alone can do the job.
@rowdy-rathore by taking lcm of 14 and 21 we get -
3 units done by a and 2 units done by b
last 3 days b did 3*2= 6 units of work.
a nd b did 42-6=36 units of work together.
so 36/5=7.2 days by both
total days =7.2+3=10.2 days.
abhisek last edited by abhisek
This post is deleted!
shraddha02 last edited by
@rowdy-rathore Can you please provide the solution to this question.