Year 7 Maths: Find what percent one number is of another

Introduction

Today, we’re going to learn how to find out what percent one number is of another. This skill will help you in many real-life situations, like calculating discounts, understanding test scores, and more. Let’s get started!

What is a Percent?

A percent means “out of 100.” So, when we say 25%, it means 25 out of 100.

Why Use Percentages?

Percentages help us compare numbers easily. For example, if you scored 80% on a test, it means you got 80 out of every 100 questions correct.

How to Find What Percent One Number Is of Another

Step-by-Step Guide

1. Identify the Two Numbers: We need to know the part and the whole.
   • Part: The number we want to find the percentage of.
   • Whole: The total number that the part comes from.
2. Use the Formula: To find the percent, we use this formula: $$\text{Percent} = \left( \frac{\text{Part}}{\text{Whole}} \right) \times 100$$
3. Perform the Calculation:
   • Divide the part by the whole.
   • Multiply the result by 100.

Example 1

Question: What percent is 20 of 50?

1. Identify the numbers:
   • Part: 20
   • Whole: 50
2. Use the formula: $$\text{Percent} = \left( \frac{20}{50} \right) \times 100$$
3. Calculate:
   • $20 \div 50 = 0.4$
   • $0.4 \times 100 = 40$

Answer: 20 is 40% of 50.

Example 2

Question: What percent is 15 of 60?

1. Identify the numbers:
   • Part: 15
   • Whole: 60
2. Use the formula: $$\text{Percent} = \left( \frac{15}{60} \right) \times 100$$
3. Calculate:
   • $15 \div 60 = 0.25$
   • $0.25 \times 100 = 25$

Answer: 15 is 25% of 60.

Key Rules

• Always identify the part and the whole.
• Make sure to multiply by 100 to get the percentage.
• If you get a decimal, that’s okay! Just remember to multiply by 100.

Tips and Tricks

• Visuals: Think of a pie chart where the whole pie is 100%. Each slice can represent a percentage of the whole.
• Practice: The more you practice, the easier it will become!

Questions

Easy Level (20 Questions)

1. What percent is 5 of 20?
2. What percent is 10 of 50?
3. What percent is 8 of 32?
4. What percent is 2 of 10?
5. What percent is 12 of 60?
6. What percent is 3 of 15?
7. What percent is 7 of 14?
8. What percent is 25 of 100?
9. What percent is 6 of 30?
10. What percent is 4 of 16?
11. What percent is 9 of 45?
12. What percent is 1 of 5?
13. What percent is 20 of 80?
14. What percent is 15 of 75?
15. What percent is 10 of 40?
16. What percent is 50 of 200?
17. What percent is 18 of 90?
18. What percent is 14 of 28?
19. What percent is 11 of 33?
20. What percent is 0 of 10?

Medium Level (20 Questions)

1. What percent is 35 of 140?
2. What percent is 60 of 120?
3. What percent is 45 of 90?
4. What percent is 75 of 150?
5. What percent is 22 of 110?
6. What percent is 50 of 200?
7. What percent is 28 of 56?
8. What percent is 30 of 90?
9. What percent is 80 of 160?
10. What percent is 55 of 110?
11. What percent is 90 of 300?
12. What percent is 66 of 132?
13. What percent is 10 of 25?
14. What percent is 12 of 48?
15. What percent is 24 of 80?
16. What percent is 40 of 160?
17. What percent is 14 of 42?
18. What percent is 33 of 99?
19. What percent is 10 of 60?
20. What percent is 50 of 250?

Hard Level (20 Questions)

1. What percent is 150 of 600?
2. What percent is 84 of 280?
3. What percent is 175 of 700?
4. What percent is 95 of 190?
5. What percent is 125 of 500?
6. What percent is 70 of 210?
7. What percent is 39 of 117?
8. What percent is 80 of 320?
9. What percent is 250 of 1000?
10. What percent is 180 of 360?
11. What percent is 65 of 130?
12. What percent is 200 of 800?
13. What percent is 90 of 450?
14. What percent is 72 of 144?
15. What percent is 110 of 220?
16. What percent is 120 of 240?
17. What percent is 300 of 1200?
18. What percent is 48 of 192?
19. What percent is 50 of 150?
20. What percent is 160 of 640?

Answers with Explanation

Easy Level Answers

1. 25%
2. 20%
3. 25%
4. 20%
5. 20%
6. 20%
7. 50%
8. 25%
9. 20%
10. 25%
11. 20%
12. 20%
13. 25%
14. 20%
15. 25%
16. 25%
17. 20%
18. 50%
19. 33.33%
20. 0%

Medium Level Answers

1. 25%
2. 50%
3. 50%
4. 50%
5. 20%
6. 25%
7. 50%
8. 33.33%
9. 50%
10. 50%
11. 30%
12. 50%
13. 40%
14. 25%
15. 25%
16. 25%
17. 33.33%
18. 33.33%
19. 16.67%
20. 20%

Hard Level Answers

1. 25%
2. 30%
3. 25%
4. 50%
5. 25%
6. 33.33%
7. 33.33%
8. 25%
9. 25%
10. 50%
11. 50%
12. 25%
13. 20%
14. 50%
15. 50%
16. 50%
17. 25%
18. 25%
19. 33.33%
20. 25%

Conclusion

Great job, everyone! Now you know how to find what percent one number is of another. Remember to practice these skills, and you will become a percentage pro in no time! If you have any questions, feel free to ask. Happy learning!