I do not see anything wrong with it
Answer:
0.
Step-by-step explanation:
Answer: it will take them 28 minutes to fill the tank.
Step-by-step explanation:
The first pipe alone can fill the tank in 84 minutes. This means that the rate at which the first pipe fills the tank per minute is 1/84
The second pipe can fill the tank in 42 minutes by itself. This means that the rate at which the second pipe fills the tank per minute is 1/42
If they work together, they would work simultaneously and their individual rates are additive. This means that their combined rate of filling the tank would be
1/84 + 1/42
Assuming it takes t hours for both pipes to fill the tank working together, the working rate per minute would be 1/t. Therefore,
1/84 + 1/42 = 1/t
3/84 = 1/t
t = 84/3
t = 28 minutes
