CBEST Math: Computation and Problem-Solving 4 — Questions and Answers
Question 1: A school has 450 students. If 54 students are absent, what percent are absent?
- 10%
- 12% (Correct answer)
- 14%
- 16%
Correct answer: 12%
54/450 = 0.12 = 12%.
Question 2: What is the least common multiple (LCM) of 8 and 12?
- 16
- 24 (Correct answer)
- 36
- 48
Correct answer: 24
The LCM of 8 and 12 is 24 because it is the smallest number divisible by both.
Question 3: A tank is 3/5 full. After adding 120 gallons, it is 4/5 full. What is the tank's total capacity?
- 400 gallons
- 500 gallons
- 600 gallons (Correct answer)
- 720 gallons
Correct answer: 600 gallons
120 gallons represents 4/5 − 3/5 = 1/5 of capacity, so total = 120 × 5 = 600 gallons.
Question 4: If the average of five numbers is 18, and four of the numbers are 14, 16, 20, and 22, what is the fifth number?
- 16
- 18 (Correct answer)
- 20
- 22
Correct answer: 18
The total is 5 × 18 = 90; the sum of the four known numbers is 72; the fifth is 90 − 72 = 18.
Question 5: Which number is NOT a prime number?
- 17
- 23
- 51 (Correct answer)
- 37
Correct answer: 51
51 = 3 × 17, so it is not prime; the others have no factors other than 1 and themselves.
Question 6: A map has a scale of 1 inch = 25 miles. Two cities are 3.6 inches apart on the map. What is the actual distance?
- 75 miles
- 80 miles
- 85 miles
- 90 miles (Correct answer)
Correct answer: 90 miles
3.6 × 25 = 90 miles.
Question 7: Simplify: (2³ × 2²) ÷ 2⁴
- 2 (Correct answer)
- 4
- 8
- 16
Correct answer: 2
2³ × 2² = 2⁵, and 2⁵ ÷ 2⁴ = 2¹ = 2.
CBEST Math: Computation and Problem-Solving 4
A school has 450 students.
If 54 students are absent, what percent are absent?