Multi-Step Measurement Problems - Pre Algebra

1. A 20 ft by 15 ft garden is covered with mulch 0.5 ft deep. How many cubic feet of mulch are needed?

   150 cubic feet, since $20 \times 15 \times 0.5 = 150$.

2. How many feet of fence are needed to enclose a 20 ft by 15 ft rectangular garden?

   70 feet, the perimeter: $2(20 + 15) = 70$.

3. A floor is 12 ft by 10 ft. Tile costs 3 dollars per square foot. What does it cost to tile the floor?

   360 dollars. The area is 120 square feet, and $120 \times 3 = 360$.

4. How many cubic feet are in 1 cubic yard?

   27 cubic feet. A cubic yard is 3 ft by 3 ft by 3 ft.

5. One can of paint covers 100 square feet. How many cans must be bought to cover 352 square feet?

   4 cans. $352 \div 100 = 3.52$, and 3 cans would not be enough, so round up.

6. A room is 10 ft by 12 ft with 8 ft high walls. What is the total area of the four walls, ignoring doors and windows?

   352 square feet, since $2(10 \times 8) + 2(12 \times 8) = 160 + 192$.

7. A tank 5 m long, 2 m wide and 1 m deep is filled with water. How many liters does it hold? (1 cubic meter = 1,000 liters)

   10,000 liters. The volume is $5 \times 2 \times 1 = 10$ cubic meters.

8. How many cubic yards are in 54 cubic feet of concrete?

   2 cubic yards, since $54 \div 27 = 2$.

9. How many square feet are in 1 square yard?

   9 square feet. A square yard is 3 ft by 3 ft.

10. What is the exact volume of a cylinder with radius 3 cm and height 10 cm?

    $90\pi$ cubic centimeters, since $V = \pi r^2 h = \pi(9)(10)$.

11. A box 2 ft by 3 ft by 4 ft is filled with sand that weighs 100 pounds per cubic foot. How much does the sand weigh?

    2,400 pounds. The volume is 24 cubic feet, and $24 \times 100 = 2400$.

12. Does wrapping a box call for its surface area or its volume, and which does filling it call for?

    Wrapping uses surface area (square units); filling uses volume (cubic units).

Study these flashcards