Question

A and b can do a work in 8 days, b and c can do the same work in 12 days. A, b and c together can finish it in 6 days. A and c together will do it in : zigya

Answer 1

a and b can do the work in 8 days
so in 1 day work done by a And b
$= \frac{1}{8}$
b and c can do work in 12 days
so in 1 day work done by b and c
$= \frac{1}{12}$
a, b and c can do work in 6 days
so in 1 day work done by a, b and c
$= \frac{1}{6}$
work done by a and b in 1 day is 1/8
and done by a, b and c is 1/6
so one day work of c
= 1/6-1/8=8-6/48=2/48=1/24
similarly work done by a in one day
1/6-1/12=12-6/72=1/12
so a one day work is 1/12
c one day work is 1/24
in 1 day they both do work
=
$\frac{1}{12} + \frac{1}{24} \\ = \frac{2 + 1}{24} \\ = \frac{3}{24} \\ = \frac{1}{8}$
so in one day they do 1/8 work
so they complete work in 8 days...