Question

The length (L) of a rectangle of fixed area varies inversely as the width (W). If the

length of the rectangle is 6 feet when the width is 12 feet, find the length of the
rectangle when the width is 4 feet.

Answer 1

Length of the rectangle is 18 ft when its width is 4ft

Explanation:

Let us assume that the length is represented by l.

Let us assume that the width is represented by w.

As given

The length of the rectangle varies inversely with its width.

Thus

L x 1/w

l=k/w

Where k is the constant of proportionality .

As given

If the

length of the rectangle is 6 feet when the width is 12 feet,

l=6, w=12

putting the values in l = k/w

6 = k/12

k = 12 x 6

k=72

As given

width is 4ft

k= 72, w = 4

Putting the values in, L = k/w

L= 72/4

L=18 ft

Therefore the length of the rectangle is 18 ft when its width is 4ft

Hope this helps You