Question

A can complete a piece of work in 36 days, B in 40 days and C in 60 days. B and C together start the work and leave the work after 4 days. Find the time taken by A to complete the remaining work?​​

Answer 1

Answer:

30 days

Step-by-step explanation:

(attachment above)

Answer 2

Given: A can complete a piece of work in 36 days, B in 40 days and C in 60 days. B and C together start the work and leave the work after 4 days.

To find: We have to find the time taken by A to complete the remaining work.

Solution:

A can complete a work in 36 days.

B can complete work in 40 days.

C can complete work in 60 days.

Thus total work will be an l.c.m of 36,40 and 60.

Thus total work is

$36 = 4 \times 3 \times 3 \\ 40 = 4 \times 5 \times 2 \\ 60 = 4 \times 5 \times 3 \\ 4 \times 5 \times 3 \times 2 \times 3\\ = 360$

Thus, the total work is 360 units.

The efficiency of A, B and C respectively 360/36, 360/40 and 360/60 means 10, 9 and 6.

In one day B and C can complete 9+6=15 unit work.

Thus in 4 days, they can compete 15×4=60 units work.

Remaining work=360-60

=300 units.

Thus A can complete the remaining work in 300/10=30 days.

Thus A can complete the remaining work in 30 days.