Tank A starts with 280 liters of water. It has a leak and is losing water at a rate of 2 liters of water per minute. At the same time, Tank B starts with 390 liters of water and also has a leak. It is losing water at a rate of 12 liters per minute. The variable t represents the time in minutes. After how many minutes will the two tanks have the same amount of water? How much water will be in the tanks at that time?

Start by writing an expression to represent the amount of water in Tank A after t minutes, where t represents the number of minutes.
Tank A

1 answer

To find the amount of water in Tank A after \( t \) minutes, we start with the initial amount of water and subtract the amount lost over time due to the leak.

Tank A starts with 280 liters of water and loses 2 liters per minute. Therefore, the expression for the amount of water in Tank A after \( t \) minutes is:

\[ A(t) = 280 - 2t \]

where \( A(t) \) represents the amount of water in Tank A after \( t \) minutes.

Next, we can write a similar expression for the amount of water in Tank B after \( t \) minutes. Tank B starts with 390 liters of water and loses 12 liters per minute. The expression for the amount of water in Tank B after \( t \) minutes is:

\[ B(t) = 390 - 12t \]

where \( B(t) \) represents the amount of water in Tank B after \( t \) minutes.

To find when the two tanks have the same amount of water, we set the two expressions equal to each other:

\[ 280 - 2t = 390 - 12t \]

Now, we can solve for \( t \):

  1. First, isolate the terms involving \( t \):

\[ 12t - 2t = 390 - 280 \]

  1. Simplify:

\[ 10t = 110 \]

  1. Divide both sides by 10:

\[ t = 11 \]

Now that we have \( t = 11 \), we can find the amount of water in either tank at that time. We'll use Tank A's expression:

\[ A(11) = 280 - 2(11) = 280 - 22 = 258 \text{ liters} \]

We can also check Tank B:

\[ B(11) = 390 - 12(11) = 390 - 132 = 258 \text{ liters} \]

Thus, after 11 minutes, both tanks will have the same amount of water, which is 258 liters.

In summary:

  • The two tanks will have the same amount of water after 11 minutes.
  • At that time, each tank will contain 258 liters of water.