OAA Mathematics 5 — Questions and Answers
Question 1: What is the surface area of a cube with side length 4 cm?
- 64 cm²
- 48 cm²
- 96 cm² (Correct answer)
- 24 cm²
Correct answer: 96 cm²
A cube has 6 faces, each with area 4² = 16 cm², so SA = 6 × 16 = 96 cm².
Question 2: Which inequality is graphed as an open circle on –3 with the arrow pointing left?
- x > –3
- x ≥ –3
- x < –3 (Correct answer)
- x ≤ –3
Correct answer: x < –3
An open circle means the value is not included (strict inequality), and the arrow pointing left represents 'less than'.
Question 3: A recipe calls for 2/3 cup of sugar. If you want to make 1.5 times the recipe, how much sugar do you need?
- 1 cup (Correct answer)
- 1 1/3 cups
- 1 1/2 cups
- 2/3 cup
Correct answer: 1 cup
2/3 × 1.5 = 2/3 × 3/2 = 6/6 = 1 cup.
Question 4: Two lines are perpendicular. One line has a slope of 2/5. What is the slope of the other line?
- 2/5
- –5/2 (Correct answer)
- 5/2
- –2/5
Correct answer: –5/2
Perpendicular lines have slopes that are negative reciprocals of each other: –5/2.
Question 5: A student earned scores of 88, 76, 94, and 82 on four tests. What score does the student need on the fifth test to have an average of 85?
- 85 (Correct answer)
- 90
- 80
- 95
Correct answer: 85
Total needed = 85 × 5 = 425; current total = 88+76+94+82 = 340; fifth score = 425 – 340 = 85.
Question 6: Which of the following represents a function?
- A circle
- {(1,2),(1,3),(2,4)}
- {(2,3),(3,3),(4,5)} (Correct answer)
- {(1,2),(2,2),(2,3)}
Correct answer: {(2,3),(3,3),(4,5)}
A function requires each input (x-value) to have exactly one output; only {(2,3),(3,3),(4,5)} satisfies this.
Question 7: What is the greatest common factor (GCF) of 36 and 48?
- 6
- 12 (Correct answer)
- 18
- 24
Correct answer: 12
Factors of 36: 1,2,3,4,6,9,12,18,36; factors of 48: 1,2,3,4,6,8,12,16,24,48; GCF = 12.
OAA Mathematics 5
What is the surface area of a cube with side length 4 cm?