Problema Solution
We have a garden that measures 17 feet by 20 feet. We want to pour cement for a 3-foot wide side walk around the garden. To make the forms for the cement, we will need to buy some 2-by-4 inch lumber. How many feet of lamber will we need just for the perimeter of the walk? (Consider both the inside and outside perimeter)
Answer provided by our tutors
the perimeter of a rectangle = 2 * ( length + width)
the inside perimeter of the walk with sides 17 and 20:
P1 = 2 * (17 + 20) = 74 ft
the outside perimeter of the walk has sides 17+3+3 and 20+3+3:
P2 = 2 * ((17 + 2*3) ) + (20 + 2*3)) = 98 ft
the total perimeter
P1 + P2 = 74 + 98 = 172 ft
we will need 172 ft of lamber for the perimeter of the walk.