Question

A water reservoir is shaped like a rectangular solid with a base that is 60 yards by 30 yards, and a vertical height of 30 yards. At the start of a three-month period of

no rain, the reservoir was completely full. At the end of this period, the height of the water was down to 6 yards. How much water was used in the three-month period?
How much water was used in the three-month period?


Please help :)

Answer 1

43200 yd³

Explanation:

The water reservoir is a rectangular solid that is a three dimensional shape with six quadrilateral faces (cuboid).

This reservoir has a base of 60 yards by 30 yards, and a vertical height of 30 yards. Therefore:

Volume of the reservoir = area of base * vertical height = 60 * 30 * 30 = 54000 yd³

This reservoir hence have a volume of 54000 yd³ when filled up with water.

After 3 months, the height of the water was down to 6 yards therefore the the volume is:

Volume after 3 months = area of base * vertical height = 60 * 30 * 6 = 10800 yd³

The amount of water used after 3 months = volume of water at beginning - volume of water after 3 months

The amount of water used after 3 months = 54000 - 10800 = 43200 yd³