Multiplying by 1 and 0
Understand the special rules for multiplying by 1 and by 0.
🎯 What You'll Learn
You will learn two special multiplication rules: any number times 1 stays the same, and any number times 0 equals 0.
🏪 Market Story
Funke asks her teacher: "What is 5 × 0?" Her teacher says, "If you have 0 bags of groundnuts, how many groundnuts do you have?" Funke thinks... "Zero! No bags means no groundnuts!" Then the teacher asks, "What about 5 × 1?" Funke says, "That's 1 bag of 5. That's just 5!"
📝 Let's Learn
Identity property (× 1): Any number times 1 equals itself.
- 7 × 1 = 7
- 100 × 1 = 100
- 1 × 53 = 53
Zero property (× 0): Any number times 0 equals 0.
- 7 × 0 = 0
- 100 × 0 = 0
- 0 × 53 = 0
Example 1: 8 × 1 = 8. One group of 8 is just 8.
Example 2: 8 × 0 = 0. Zero groups of 8 is nothing at all.
Example 3: Tunde buys 1 bag of rice at ₦200. Total: 1 × ₦200 = ₦200.
✏️ Practice Questions
- What is 25 × 1?
- What is 50 × 0?
- Chidi has 0 bags. Each bag has 10 oranges. How many oranges does he have?
Click to see answers
- 25 × 1 = 25.
- 50 × 0 = 0.
- 0 × 10 = 0 oranges. No bags means no oranges!
💡 Remember
Times 1 = the same number. Times 0 = zero. These two rules work for every number, no matter how big!