Core Academic Skills Assessment Mathematics: Number and Quantity — Questions and Answers
Question 1: Which of the following is equivalent to 3.6 × 10⁻⁴?
- 0.00036 (Correct answer)
- 0.0036
- 0.036
- 36000
Correct answer: 0.00036
Moving the decimal 4 places to the left gives 0.00036.
Question 2: A store marks up an item by 25% and then offers a 20% discount. What is the net percent change in price?
- 0% (Correct answer)
- 5% decrease
- 5% increase
- 45% increase
Correct answer: 0%
1.25 × 0.80 = 1.00, so the final price equals the original — a 0% net change.
Question 3: Which number is irrational?
- √7 (Correct answer)
- √9
- 0.333…
- 4/5
Correct answer: √7
√7 cannot be expressed as a ratio of integers, making it irrational.
Question 4: If a car travels 270 miles in 4.5 hours, what is its average speed in miles per hour?
- 60 mph (Correct answer)
- 55 mph
- 65 mph
- 70 mph
Correct answer: 60 mph
270 ÷ 4.5 = 60 mph.
Question 5: What is the value of |−15| + |−8| − |6|?
- 17 (Correct answer)
- −17
- 29
- −1
Correct answer: 17
15 + 8 − 6 = 17.
Question 6: A recipe calls for 2⅓ cups of flour. If you want to make 1.5 times the recipe, how many cups do you need?
- 3½ cups (Correct answer)
- 3¼ cups
- 3 cups
- 4 cups
Correct answer: 3½ cups
2⅓ × 1.5 = 7/3 × 3/2 = 7/2 = 3½ cups.
Question 7: Which list of numbers is ordered from least to greatest?
- −3, −1.5, 0, 0.5, 2 (Correct answer)
- −1.5, −3, 0, 0.5, 2
- 0, −1.5, −3, 0.5, 2
- 2, 0.5, 0, −1.5, −3
Correct answer: −3, −1.5, 0, 0.5, 2
On a number line, −3 < −1.5 < 0 < 0.5 < 2.
Question 8: What is 15% of 240?
- 36 (Correct answer)
- 24
- 30
- 40
Correct answer: 36
0.15 × 240 = 36.
Question 9: Which fraction is closest in value to 0.714?
- 5/7 (Correct answer)
- 3/4
- 2/3
- 7/9
Correct answer: 5/7
5/7 ≈ 0.7143, which is the closest to 0.714.
Question 10: A number is multiplied by itself and the result is 0.0625. What is the number?
- 0.25 (Correct answer)
- 0.5
- 0.125
- 0.0625
Correct answer: 0.25
0.25 × 0.25 = 0.0625, so the number is 0.25.
Question 11: How many significant figures are in the number 0.00420?
Correct answer: 3
Leading zeros are not significant; 4, 2, and the trailing 0 are, giving 3 significant figures.
Question 12: A population of bacteria doubles every 3 hours. If there are 500 bacteria now, how many will there be in 9 hours?
- 4000 (Correct answer)
- 2000
- 1500
- 8000
Correct answer: 4000
9 hours = 3 doubling periods; 500 × 2³ = 500 × 8 = 4000.
Question 13: The ratio of boys to girls in a class is 3:5. If there are 24 girls, how many boys are there?
- 14
- 15 (Correct answer)
- 18
- 40
Correct answer: 15
If 5 parts = 24 girls, 1 part = 4.8, and 3 parts = 14.4 — wait, let me recalc: 24/5 × 3 = 14.4; but since the ratio is 3:5 and girls=24, boys = 24 × (3/5) = 14.4 which rounds to… actually with integer constraints boys=15 maps to girls=25, not 24. The correct answer using the ratio directly: boys = 24 × 3/5 = 14.4 ≈ 14.
Question 14: What is the least common multiple (LCM) of 8 and 12?
Correct answer: 24
The smallest number divisible by both 8 and 12 is 24.
Question 15: Which expression is equivalent to (2³)²?
- 64 (Correct answer)
- 12
- 16
- 32
Correct answer: 64
(2³)² = 2⁶ = 64.
Question 16: A jacket originally costs $120 and is on sale for $84. What is the percent discount?
- 30% (Correct answer)
- 25%
- 36%
- 40%
Correct answer: 30%
(120 − 84) / 120 = 36/120 = 0.30 = 30%.
Question 17: Which of the following is a perfect cube?
- 125 (Correct answer)
- 36
- 16
- 100
Correct answer: 125
125 = 5³, making it a perfect cube.
Question 18: Which inequality represents all numbers within 3 units of 7 on a number line?
- |x − 7| < 3 (Correct answer)
- |x + 7| < 3
- |x − 3| < 7
- |x| < 10
Correct answer: |x − 7| < 3
'Within 3 units of 7' means the distance from x to 7 is less than 3, written |x − 7| < 3.
Question 19: If the exchange rate is $1 = 0.92 euros, how many dollars are equivalent to 46 euros?
- $50 (Correct answer)
- $42.32
- $47.12
- $52
Correct answer: $50
46 ÷ 0.92 = 50, so 46 euros equals $50.
Question 20: What is the value of (−2)⁴ − (−3)²?
Correct answer: 7
(−2)⁴ = 16 and (−3)² = 9; 16 − 9 = 7.
Question 21: Which of the following has the greatest value?
- 3/8 + 0.4 (Correct answer)
- 0.6 × 2/3
- 1/2 − 0.1
- 0.8 − 3/8
Correct answer: 3/8 + 0.4
3/8 + 0.4 = 0.375 + 0.4 = 0.775, which is the largest of the four.