Question

Matt plans to put concrete on a rectangular portion of his driveway. The portion is 8 feet long and 4 inches high. The price of concrete is $98 per cubic yard. The total cost of the concrete Matt needs is $58.07. Which of the following is closest to the width of the portion of the driveway on which Matt plans to put concrete?. . [1 foot = 12 inches; 1 yard = 3 feet]. a. 0.5 feet. b. 1.5 feet. c. 3 feet. d. 6 feet

Answer 1

Convert first the cost of $98 /yd³ by the conversion factor that 1 yd³ = 27 ft³.
                           ($98 /yd³) (1 yd³ / 27 ft³) = $ 3 17/27/ft³
Let x be the width, the volume of the rectangular portion of the driveway is,
                           V = (8 ft) (1/3 ft) x = 8x/3 ft³
Using the given total cost of the protion,
                                  C = $58.07 = (8x/3 ft³)($ 3 17/27/ft³) 
x = 5.99957 ft
Thus, the answer is d. 6 feet.

Answer 2

1 cubic yard = 27 cubit feet

then we must find the no.of cubic yards

for 1 cubic yard = $98
for "x" cubic yard = $58.07

1/x =98/58.07
x = 0.5925

Now we have to convert this in to cubic feet...
1 cubic yard = 27 cubic feet
0.5925 cubic yard = x cubic feet

1/0.5925= 27/x
x = 15 .99 cubic feet

now

width x height x length = 16 cubic feet
w x 8 x (1/3) = 16
w = 48/8 = 6 feet

yep! there for the width of the yard is approximately 6 feet..