Question

A and b can do a piece of work 20,30,60 respectively in how many can a do the work if he assisted by b and c on every 3rd day

Answer 1

A-20

B-30

C-60

L.C.M of A,B,$C =60work

EFFICIENCY OF A,B and C are 3,2 and 1

so

if a work all days and b $ c assist in per 3 days

(3+3+6)*5=60 work

so this work completed in 15days