A can do 40% of a work in 12 days,
whereas B can do 60% of the same work
in 15 days. Both work together for 10
days. C completes the remaining work
alone in 4 days. A, B and C together will complete 28% of the same work in:

2 days

2 days

2 days.

A takes 30 days for full work
B takes 25 days for full work
LCM is 150.. so assume total work is 150 units
A does 5units/ day
B does 6u/ day

10 days together ==> 110 units. pending is 40 units which C completes in 4 days. C therefore does 10u/days/

28% of 150 is 42 units.. total units by ABC in a day is 6+5+10= 21..
so days is 42/21 =2 days