18 inches= 1 1/2 feet= 1.5 feet
18 inches = 1.5 feet
(1) Now we make a proportion to find feet for given inches
\(\frac{feet}{inches} = \frac{feet}{inches}\)
\(\frac{1.5}{18} = \frac{x}{36}\)
1.5 36 = 18x
54 = 18 x (Divide by 18 on both sides)
x = 3
3 feet long is a 36 inch board
(2) 72 inch board
\(\frac{1.5}{18} = \frac{x}{72}\)
1.5 72 = 18x
108 = 18 x (Divide by 18 on both sides)
x = 6
6 feet long is a 72 inch board
(3) 144 inch board
\(\frac{1.5}{18} = \frac{x}{144}\)
1.5 144 = 18x
216 = 18 x (Divide by 18 on both sides)
x = 12
12 feet long is a 144 inch board
