Question

Andrei has a glass tank. First he wants to put in some marbles, each of which has a volume of 0.04 liters. Then he wants to fill the tank with water until its completely full. If he uses 50 marbles, he will have to add 33 liters of water.

1. What is the volume of the tank?

2. Andrei has exactly 20 liters of water. How many marbles does he need so the tank is full?​

Answer 1

The necessary amount of water decreceas at the same rate over both intervals

Explanation:

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Answer 2

The tank has a volume of 35 L and in part 2) he would need 375 marbles.

Explanation:

1) Each marble occupies a volumes of 0.04 L so 50 marbles occupy 50 times 0.04 L = 2 L.

Since he neede 33 L of water to fill the thank, it follows the total volume will be 33 L plus 2 L or 35 L

2) We need 15 L of volume of marbles since we only have 20 Liters of water. Therefore what is needed is to calcuculate how many marbles have 15 L of marbles:

15 L x 1 marble per 0.04 L = 15/.04 marbles = 375 marbles