Louise measured the perimeter of her rectangular scrapbook to be 140 cm. If the scrapbook is 40 cm wide, how long is the scrapbooK
Let's assume that the length of the scrapbook is "L" cm.
The perimeter of a rectangle is given by the formula:
Perimeter = 2(L + W)
where L is the length and W is the width.
We are given that the width of the scrapbook is 40 cm and the perimeter is 140 cm.
Substituting these values in the formula, we get:
140 = 2(L + 40)
Simplifying the equation, we get:
L + 40 = 70
L = 70 - 40
L = 30
Therefore, the length of the scrapbook is 30 cm.
To find the area of the scrapbook, we can use the formula:
Area = Length x Width
Substituting the values, we get:
Area = 30 x 40
Area = 1200 cm²
Therefore, the area of the scrapbook is 1200 cm².