Question

An inlet pipe can fill a tank in 15 minutes. A drain can empty the tank in 18 minutes. If the tank is empty, and both the pipe and drain are open, how long will it take before the tank overflows?

Answer 1

i believe you use the formula \[\frac tx - \frac ty = 1\]
where x is the filling pipe and y is the emptying pipe. t is the total time it takes to be fll

\[\frac{t}{15} - \frac{t}{18} = 1\]
\[\frac{18t}{270} - \frac{15t}{270} = 1\]
\[\frac{18t - 15t}{270} = 1\]
\[\frac{3t}{270} = 1\]
\[3t = 270\]
\[t = \frac{270}{3}\]
\[t = 90 \; \text{minutes}\]

Answer 2

did you get htat?

Answer 3

no

Answer 4

what didnt you get?

Answer 5

what would the answer be because 90 is not the answer

Answer 6

it needs to be in hours the answer needs to be in hours

Answer 7

how many minutes in 1 hour?

Answer 8

60

Answer 9

therefore just subtract that from 90

90 - 60 = 30

therefore 90 minutes = 1 hour and 30 minutes

Answer 10

that answer is wrong webassign is not accepting it as the answer. Is there another approach to take to solve this problem?

Answer 11

try 1.5 hours

Answer 12

yea thanks it works do you mind helping me out with another problem similar to this one please

Answer 13

well i have to go now sorry

Answer 14

ok thanks anyways