Question

A does half as much work as b in three-fourth of time. If together they take 18 days to complete a work , how much time shall b take to do it alone ? Answer short cut

Answer 1

Answer:

B takes 45 days to the same work alone.

Step-by-step explanation:

1/A + 1/B = 1/18 (Given)

(2/4B/3) + 1/B = 1/18

3/2B + 2/2B = 1/18 (Short-cut method)

5/2B = 1/18

B = 90/2 = 45 days

Hence, B takes 45 days to the same work alone.

Answer 2

Answer:

24.75 day

Step-by-step explanation:

A does half as much work as b in three-fourth of time. If together they take 18 days to complete a work

Let say B do work in 3/4 Day  = x

b do work in 1 day = 4x/3

A do work in 1 day = x/2

Both together do in 1 day  = 4x/3 + x/2 = (8x + 3x)/6 = 11x/6

Both together do in 18 day = 18 * 11x/6 = 33x

Total work = 33x

B do  4x/3   in   1 day

B do  1  in   1/(4x/3)  = 3/4x

b do 33x  in  =  33 * 3/4x  = 24.75 day

b alone will do in 24.75 days