The question is
What are the dimensions of the original rectangle?
Step 1
<u>Find the scale factor</u>
we know that
The scale factor is equal to

we have


Substitute the values

therefore
the scale factor is 
Step 2
<u>Find the width of the reduced rectangle</u>
we know that
The perimeter of a rectangle is equal to

where
L is the length side of the rectangle
W is the width side of the rectangle
Reduced rectangle
we have


substitute


Solve for W


therefore
The dimensions of the reduced rectangle are 
Step 3
<u>Find the dimensions of the original rectangle</u>
Original Length
we know that

we have


substitute

Original Width
we know that

we have


substitute

therefore
The dimensions of the original rectangle are 