Question

Length of a rectangular prism is increased by factor of 1.5. The width is doubled and height is tripled. What is the new volume?

1) double the original volume
2) triple the original volume
3) six times the original volume
4) nine times the original volume

Answer 1

Nine times the original volume

Explanation:

Let the length, width and height of the rectangular prism be 'l' 'w' and 'h'.

The volume of the rectangular prism is given by,

V = W x l x h

The original volume of the rectangular prism is,

V = wlh

Here the length is 1.5 the original length

So, l = 1.5 x l = (1.5l)

And the with is doubled. So,

W = 2W

The height is tripled. So,

h = 3h

Volume of the new rectangular prism is,

V = (1.5l) (2w) (3h)

V = 9 wlh

We know that wlh is the original volume of the rectangular prism.

So the new volume is 9 times the original volume.