Two taps 'a' and 'b' can fill a water tank in 9min and 12 min respectively.In what time it will be full, if 'b' starts working 2 min after 'a' starts working?...........
Two taps 'a' and 'b' can fill a water tank in 9min and 12 min respectively.In what time it will be full, if 'b' starts working 2 min after 'a' starts working?...........
Let T denote the volume of the tank.
Then a delivers per minute and
b delivers per minute.
After x minutes the tank is filled:
. Divide by T, expand the brackets, collect like terms: