Practice Test Discussion

Q)

A and B can do a piece of work in 72 days. B and C can do the same work in 120 days. A and C can do it in 90 days. In what time can A alone do it?

[SSC 2011]


  • Explanation

    In the given problem in 1 day,

    (A+B) can do 172 part of work

    (B+C) can do 1120 part of work

    (C+A) can do 190 part of work,

    So, in one day, 2(A+B+C) can do,

    2(A+B+C)=172+1120+190A+B+C=5+3+4360×2=12360×2=160

    1 day work of A=[1 day work of (A+B+C)]-[1 day work of (B+C)]

    160-1120=2-1120=1120

    Hence, A alone can finish te work in 120 days

    Hence option C is correct

     

    For more Short tricks and formulae click 

    Work and Time

    - Share with your friends! -

    Login to post your comment here...

    Comments