Question

two inlet pipes can eperately fill atank in 20 and 15 minand a waste pipe can empty the filled tankin 12 min. on a certain day, the two inlet pipes are turned on simultaneously to fill the empty tank . but after 9 min it was found that the waste pipewas also left opened , it was closed immediately . how much additional tank is required to fill the tank completely

Answer 1

Answer:

so it will take 30 hours to fill the tank

Step-by-step explanation:

So A is 20/15 = 1,33 times faster than B

and A is 12/15 = 0,8 times as fast outlet pipe

so in relation to A - we are using A’s time only everything else is in relation to A

Let X = time taken to fill tank

X ( 1 + 1/1,33 - 1/0,8) = 15

X ( 1 + 0,75 - 1,25) =15

0,5 X = 15

X = 30

so it will take 30 hours to fill the tank