Perimeter of a rectangle= 2(length)+2(width)
Data:
Perimeter=108 cm
length=18 cm
therefore:
108 cm=2(18 cm)+2(width)
108 cm=36 cm+2 (width)
2 width=108 cm -36 cm=
2 width=72 cm
width=72cm/2
width=36 cm
Answer: the width of the picture frame would be 36 cm.
The key concept you must have to remember is that, the rate is kept constant, as what is specified in the problem. Our basis for the rate is the first situation.
Rate = 20 facts/ 1 min.
Let's equate this to the second situation using x as the time unknown.
20/1 = 35/x
Solving for x,
<em>x = 1.75 minutes</em>
