# ACT Math : How to find the volume of a prism

## Example Questions

### Example Question #5 : How To Find The Volume Of A Prism

A rectangular box has  sides whose lengths are  and , and a volume of .

What is the area of its largest side?

Explanation:

We take the volume, , divide by , then again by  giving the last length of .

This makes the dimensions of the sides either  by ,  by , or  by , making the greatest area of one of the sides .

### Example Question #1 : How To Find The Volume Of A Prism

A box's length is twice as long as its width. Its height is the sum of its length and its width. What is the volume of this box if its length is 10 units?

units cubed

units cubed

units cubed

units cubed

units cubed

units cubed

Explanation:

The formula for the volume of a rectangular prism is , where "" is volume, "" is length, "" is width and "" is height.

We know that  and . By rearranging , we get . Substituting  into the volume equation for  and  into the same equation for , we get the following:

units cubed

### Example Question #2 : How To Find The Volume Of A Prism

A rectangular prism has the following dimensions:

Length:

Width:

Height:

Find the volume.

Explanation:

Given that the dimensions are: , , and  and that the volume of a rectangular prism can be given by the equation:

, where  is length,  is width, and  is height, the volume can be simply solved for by substituting in the values.

This final value can be approximated to .

### Example Question #3 : How To Find The Volume Of A Prism

A prism that is 4m by 3m by 8m has a volume of what?

Explanation:

The volume of the rectangle

so we plug in our values and obtain

.