Question

A do a work in 5 days.B do in 3 days. With the help of c do in 4 days

Answer 1

A does in 5 days
A's 1 day work = 1/5
B does in 3 days
B's 1 day work = 1/3
C does in 4 days
C's 1 day work = 1/4
(A+B+C)'s 1 day work =
$( \frac{1}{5} + \frac{1}{3} + \frac{1}{4} ) \\ = \frac{12 + 20 + 15}{60} \\ \frac{47}{60}$
time taken to complete the same work = 1/1days work
$= \frac{1}{ \frac{47}{60} } = \frac{1}{1} \times \frac{60}{47} \\ = \frac{60}{47} = 1 \frac{13}{47} days$