Question

Two pipes can fill a tank in 98 98 minutes if both are turned on. If only one is used, it would take 29 29 minutes longer for the smaller pipe to fill the tank than the larger pipe. How long will it take for the smaller pipe to fill the tank?

Answer 1

63.5minutes

Explanation:

Let the time it takes the small pipe to fill the tank be x

Let the time it takes the larger pipe to fill the tank be y

If the two pipes can fill a tank in 98 minutes if both are turned on then:

x+y = 98...1

If only one is used and it takes 29 minutes longer for the smaller pipe to fill the tank than the larger pipe

x = 29+y... 2

Substituting equation 2 into 1 to get y we have:

29+y+y = 98

29+2y = 98

2y = 98-29

2y = 69

y = 69/2

y = 34.5minutes

x = 29+34.5

x = 63.5

This means it will take the smaller pipe 63.5minutes to fill the tank