Question

Finding a perimeter of similar rectangles using a scale factor?

The question is:
Two similar rectangles have a scale factor of 5 : 4, the larger of the two rectangles is 6.8 inches long and 3.1 inches wide.
Determine the perimeter, in inches, of the smaller of the two rectangles.

Thanks!

Answer 1

Perimeter is `15.84` inches

Explanation:

`"Larger rectangle":"Smaller rectangle" = 5:4`

So basically, the smaller rectangle is `4/5` the length of breadth of the larger rectangle

ie `5:4 = 5/5:4/5 = 1:4/5`

Therefore, the length of the smaller rectangle is:

`6.8times4/5 = 5.44` inches

And the width is:

`3.1times4/5=2.48` inches

So, to calculate your perimeter which is:

`2times"length" + 2times"width"`
= `2times5.44+2times2.48=15.84` inches