Question

Two pipes can fill a tank in 10 and 12 hours respectively while a third pipe empty the full tank in 20 hours if all the three pipes are opened mutants lee in how much time the tank will be filled

Answer 1

Hlw mate !!


l.c.m of 3 pipes is(10,12,20) is 60

efficiency of pipe a is 60/10=6
efficiency of pipe b is 60/12 =5
pipe c is 60/20 =3

so a=6
b=5
c=3

(filling pipe - empty pipe)
that is 6+5-3=8

then 60(l.c.m)/8
60/8=7.5 hrs
correct ans is 7.5



Hope it helpful