---------------------------------------------------------------------- Given information ---------------------------------------------------------------------- 20 feet cost $36
---------------------------------------------------------------------- Find the cost of 1 foot by dividing by 20 ---------------------------------------------------------------------- 20 feet = $36 1 foot = $36 ÷ 20 1 foot = $1.8
---------------------------------------------------------------------- Find the cost of 15 feet by multiplying by 15 ---------------------------------------------------------------------- 1 foot = $1.80 15 feet = $1.80 x 15 15 feet = $27
If 20 feet cost $36 then you can divide 36 by 20 to see how much one foot would cost. The answer is $1.80. Then multiply $1.80 x 15 feet and you get $27