A pond is enclosed by a wooden deck that is 3 feet wide. The fence surrounding the deck is 100 feet long. If the pond is rectangular and the length of the pond is to be three times its width, what are its dimensions?

Answer 1

width of pond --- x
length of pond --- 3x

width of whole thing = x+6 , (3 feet on each end)
length = 3x + 6

2(x+6) + 2(3x+6) = 100
2x + 12 + 6x + 12 = 100
8x = 76
x = 9.5 ft

the pond is 9.5 ft wide and 28.5 ft long