Problema Solution
What is the cost of concrete for a walkway that is 15 feet long, 8 feet wide, and 9 inches deep if the concrete costs $30 per cubic yard?
Answer provided by our tutors
let
l = 15 ft length
w = 8 ft width
d = 9 in = 9(1/12) ft (since 1 ft = 12 in)
the volume of the concrete is:
V = l*w*d
V = 15*8*9*(1/12)
V = 90 ft^3
1 yd = 3 ft
1 yd^3 = 3^3 ft^3
thus $30 are paid for 9 ft^3 and for 10 times this amount we have:
10*$30 = $300 will be the cost of 10*9 = 90 ft^3
the cost of the concrete is $300.