Question

5. A glass aquarium is in the form of a rectangular parallelepiped with dimensions 50cm by 100cm, and its depth is 30cm. How many liters does it contain when the depth of water is 15cm?

Answer 1

Hello! First, let's draw the aquarium:

As we did before, we first have to find the volume of the aquarium, using the formula:

Volume = a * b * c

Volume = 100 * 50 * 30

Volume = 150,000cm³, which means the total capacity equals 150 liters (aquarium full of water).

Now, we want to know how many liters when the depth is 15cm, instead of 30cm as we already calculated. So, we have two ways to find this:

1st way:

We will replace where is 30cm in the formula, and now put 15cm:

Volume = a * b * c

Volume = 100 * 50 * 15

Volume = 75,000cm³ = 75 liters

2nd way:

As we know that the full capacity is 150 liters when the water depth is 30cm, we will divide 150 by two, as 30/15 = 2.

So, we'll find 150/2 = 75 liters