Question

2. Tap A fill tank in 6mins, Tap B fill in 9mins. Pipe C empty the tank in 15mins, what is the time taken to fill up the tank when the 2 taps and pipe are in the tank ?

Answer 1

da/dt = 6
db/dt = 9
dc/dt = -15

Answer 2

am i heading in the right direction ?

Answer 3

is the answer \(4.73~min\) i need to confirm

Answer 4

the part filled in 1 min =\(\dfrac{1}{9}+\dfrac{1}{6}-\dfrac{1}{15}=\dfrac{19}{90}\)

and the time taken to fill it is \(\dfrac{90}{19}\)

Answer 5

so its equal to 4 min 44 sec

Answer 6

please @HatcrewS if you kno chinese could you please help meh there is no one in the chinese subject.