College Math Placement Test Arithmetic 4 — Questions and Answers
Question 1: A number is decreased by 40% and the result is 48. What was the original number?
- 67.2
- 80 (Correct answer)
- 120
- 96
Correct answer: 80
If x × (1 − 0.40) = 48, then x × 0.60 = 48, so x = 48 / 0.60 = 80.
Question 2: Simplify: (3/4 + 1/6) × 12
- 9
- 11 (Correct answer)
- 10
- 12
Correct answer: 11
3/4 + 1/6 = 9/12 + 2/12 = 11/12; (11/12) × 12 = 11.
Question 3: What is the median of the data set: 3, 7, 7, 2, 9, 4, 1?
- 4 (Correct answer)
- 7
- 3
- 5
Correct answer: 4
Ordered: 1, 2, 3, 4, 7, 7, 9; the middle (4th) value is 4.
Question 4: Which expression is equivalent to 2⁵ × 2³?
- 4⁸
- 2¹⁵
- 2⁸ (Correct answer)
- 4¹⁵
Correct answer: 2⁸
When multiplying powers with the same base, add exponents: 2⁵ × 2³ = 2⁸.
Question 5: Sam earns $15/hour and works 38 hours per week. How much does he earn in 4 weeks?
- $2,100
- $2,400
- $2,280 (Correct answer)
- $2,160
Correct answer: $2,280
Weekly earnings = 15 × 38 = $570; over 4 weeks: 570 × 4 = $2,280.
Question 6: What is 5/6 − 2/9?
- 3/18
- 11/18 (Correct answer)
- 1/2
- 7/18
Correct answer: 11/18
LCD of 6 and 9 is 18; 15/18 − 4/18 = 11/18.
Question 7: A rectangle's length is twice its width. If the perimeter is 48 cm, what is the width?
- 12 cm
- 8 cm (Correct answer)
- 16 cm
- 6 cm
Correct answer: 8 cm
Let width = w; then length = 2w; perimeter = 2(w + 2w) = 6w = 48, so w = 8.
College Math Placement Test Arithmetic 4
A number is decreased by 40% and the result is 48.
What was the original number?