BMST - Basic Math and Science Ratios, Proportions, and Percentages Questions and Answers 2 — Questions and Answers

Question 1: What is 35% of 200?

70 (Correct answer)
35
7000
7

Correct answer: 70

35% × 200 = 0.35 × 200 = 70.

To find a percentage of a number, convert the percentage to a decimal (divide by 100) and multiply: 35% = 0.35, then 0.35 × 200 = 70. Alternatively, you can find 10% (20) and multiply by 3.5: 20 × 3.5 = 70. Understanding percentage calculations is essential for daily math like discounts, taxes, and tips.

Question 2: Simplify the ratio 24:36.

2:3 (Correct answer)
3:4
4:6
12:18

Correct answer: 2:3

Divide both numbers by their GCF (12): 24÷12 = 2, 36÷12 = 3.

To simplify a ratio, divide both terms by their greatest common factor (GCF). For 24:36, the GCF is 12. So 24÷12 = 2 and 36÷12 = 3, giving the simplified ratio 2:3. While 4:6 and 12:18 are equivalent ratios, 2:3 is the simplest form because 2 and 3 share no common factors other than 1.

Question 3: If 3 pencils cost $1.50, how much do 8 pencils cost?

$4.00 (Correct answer)
$3.50
$5.00
$4.50

Correct answer: $4.00

Unit price = $1.50 ÷ 3 = $0.50. Cost of 8 = 8 × $0.50 = $4.00.

This is a proportion problem. First find the unit rate: $1.50 ÷ 3 pencils = $0.50 per pencil. Then multiply by the desired quantity: $0.50 × 8 = $4.00. Alternatively, set up a proportion: 3/1.50 = 8/x, cross-multiply: 3x = 12, x = 4. Both methods give $4.00.

Question 4: A shirt originally costs $60 and is on sale for 25% off. What is the sale price?

$45 (Correct answer)
$35
$15
$48

Correct answer: $45

Discount = 25% of $60 = $15. Sale price = $60 - $15 = $45.

To find a sale price after a percentage discount: calculate the discount amount (25% × $60 = $15), then subtract from the original price ($60 - $15 = $45). Alternatively, the sale price is 75% of the original (100% - 25% = 75%): 0.75 × $60 = $45. Both methods work; the second is often faster.

Question 5: The ratio of boys to girls in a class is 3:5. If there are 24 students, how many are boys?

9 (Correct answer)
15
12
8

Correct answer: 9

Total parts = 3 + 5 = 8. Each part = 24 ÷ 8 = 3. Boys = 3 × 3 = 9.

The ratio 3:5 means for every 3 boys there are 5 girls (8 students total per group). Total ratio parts = 3 + 5 = 8. Each part represents 24 ÷ 8 = 3 students. Boys = 3 parts × 3 students = 9 boys. Girls = 5 parts × 3 students = 15 girls. Check: 9 + 15 = 24.

Question 6: What is 15 as a percentage of 60?

25% (Correct answer)
15%
40%
4%

Correct answer: 25%

(15 ÷ 60) × 100 = 0.25 × 100 = 25%.

To express one number as a percentage of another, divide the part by the whole and multiply by 100: (15/60) × 100 = 0.25 × 100 = 25%. This means 15 is 25% of 60. You can verify: 25% of 60 = 0.25 × 60 = 15. This type of calculation is used in statistics, grading, and financial analysis.

BMST - Basic Math and Science Ratios, Proportions, and Percentages Questions and Answers 2

What is 35% of 200?