Let’s write an expression to represent the number of liters left in Tank A after t minutes, where t represents the number of minutes. We’ll go step by step. How much water starts in Tank A?

Question

Tank A
starts with 400 liters
leaking 3 liters per minute

?
+ ?
Tank B
starts with 180 liters
filling 5 liters per minute

Answer 1

To represent the number of liters left in Tank A after \( t \) minutes, we start with the initial amount of water in the tank and then account for the rate at which it is leaking.

1. Initial amount of water in Tank A: 400 liters.
2. Rate of leakage from Tank A: 3 liters per minute.

The expression to calculate the amount of water left in Tank A after \( t \) minutes subtracts the total amount leaked over that time from the initial amount.

The amount leaked after \( t \) minutes is given by: \[ \text{Amount leaked} = \text{leak rate} \times t = 3 , \text{liters/minute} \times t \]

Thus, the amount of water left in Tank A after \( t \) minutes can be expressed as: \[ \text{Liters left in Tank A} = \text{Initial amount} - \text{Amount leaked} \] \[ \text{Liters left in Tank A} = 400 - (3t) \]

Therefore, the expression for the number of liters left in Tank A after \( t \) minutes is: \[ 400 - 3t \]