Crossover Aptitude Test Math 3 — Questions and Answers
Question 1: The average of five numbers is 18. Four of them are 14, 20, 22, and 16. What is the fifth number?
- 16
- 18 (Correct answer)
- 20
- 22
Correct answer: 18
Total sum = 5 × 18 = 90; 90 - 72 = 18.
Question 2: A rectangle has a perimeter of 48 cm and a width of 10 cm. What is its area?
- 140 cm² (Correct answer)
- 160 cm²
- 180 cm²
- 200 cm²
Correct answer: 140 cm²
Length = (48/2) - 10 = 14 cm; Area = 14 × 10 = 140 cm².
Question 3: Solve for x: 3(x - 4) = 2x + 1
- 11
- 13 (Correct answer)
- 9
- 15
Correct answer: 13
3x - 12 = 2x + 1, so x = 13.
Question 4: A train travels from City A to City B in 3 hours at 80 mph. What is the distance?
- 200 miles
- 220 miles
- 240 miles (Correct answer)
- 260 miles
Correct answer: 240 miles
Distance = 80 × 3 = 240 miles.
Question 5: What is the least common multiple (LCM) of 12 and 18?
- 24
- 36 (Correct answer)
- 54
- 72
Correct answer: 36
12 = 2²×3, 18 = 2×3²; LCM = 2²×3² = 36.
Question 6: If f(x) = 2x² - 3, what is f(-3)?
- 15 (Correct answer)
- 21
- 12
- 9
Correct answer: 15
f(-3) = 2(9) - 3 = 18 - 3 = 15.
Question 7: A number is increased by 25% and then decreased by 25%. What is the net percentage change?
- No change
- 6.25% decrease (Correct answer)
- 6.25% increase
- 3.125% decrease
Correct answer: 6.25% decrease
1.25 × 0.75 = 0.9375, a 6.25% decrease from the original.
Crossover Aptitude Test Math 3
The average of five numbers is 18.
Four of them are 14, 20, 22, and 16.
What is the fifth number?