Question

See attachment.

Answer 1

Jack takes 6 hors to complete the work
which means he does 1/6 th work in an hour, similarly marilyn does 1/4th work in an hour.
together they will do 1/6 +1/4 work
in one hour they do 5/12 work
so they will complete the work in 12/5 hours or 2.4 hours
or 2 hours 24 minutes

Answer 2

So if 2hrs& 24min is the answer how do i wright that in the box?