CAST Math 3 — Questions and Answers
Question 1: Convert the fraction 7/8 to a decimal.
- 0.785
- 0.825
- 0.875 (Correct answer)
- 0.925
Correct answer: 0.875
7 ÷ 8 = 0.875.
Question 2: A motor runs at 1,800 RPM. How many revolutions occur in 15 seconds?
- 360
- 450 (Correct answer)
- 480
- 540
Correct answer: 450
1,800 RPM = 30 revolutions per second, and 30 × 15 = 450.
Question 3: What is the perimeter of a square with sides of 13 inches?
- 39 in
- 42 in
- 52 in (Correct answer)
- 56 in
Correct answer: 52 in
Perimeter = 4 × side = 4 × 13 = 52 inches.
Question 4: A part costs $4.80 and you buy 25 of them. What is the total cost?
- $108
- $112
- $120 (Correct answer)
- $125
Correct answer: $120
4.80 × 25 = $120.
Question 5: Solve for y: y/4 + 3 = 10.
- 20
- 24
- 28 (Correct answer)
- 32
Correct answer: 28
Subtract 3 to get y/4 = 7, then multiply by 4 to get y = 28.
Question 6: A pipe has an inside diameter of 6 inches. What is its radius?
- 2 inches
- 3 inches (Correct answer)
- 4 inches
- 6 inches
Correct answer: 3 inches
Radius is half the diameter, so 6 ÷ 2 = 3 inches.
Question 7: If a measurement reads 0.75 inches, how many sixteenths of an inch is that?
- 8/16
- 10/16
- 12/16 (Correct answer)
- 14/16
Correct answer: 12/16
0.75 × 16 = 12, so 0.75 inch equals 12/16.
CAST Math 3
Convert the fraction 7/8 to a decimal.