Idea 3of 24Builds onTurn the array, keep the product
Times 0 and times 1
What happens when you multiply by 1, or by 0?
Today you'll discover
- why 1 × 8 is 8
- why 0 × 8 is 0
- why you cannot divide by 0
Think firstOne row of 8 counters
One row of 8 counters. What is 1 × 8?
Decide first, then press Next. Count the groups, then what is in each.
One row of 8 dots, labelled 1 row and 8 in each row, then 1 × 8. Then an empty dashed box for 0 rows of 8, with 0 × 8 = 0. The last step shows 12 empty dashed rows.
See the whole ideathe big idea and the key word, in one place
The big idea
Any number times 1 is itself; any number times 0 is 0.
For example1 × 12 = 12 and 12 × 1 = 12. 0 × 12 = 0 and 12 × 0 = 0.
Easy to get wrongYou cannot divide by 0: 8 ÷ 0 asks to share 8 among no one, which has no answer. But 0 ÷ 8 = 0.
Key words
- times 1
- one group of a number: the number stays the same, so 1 × 8 = 8
- times 0
- no groups, or groups with nothing in them: the product is always 0
Ready to use it?
- Multiply any number by 0 or by 1.
- Spot a division by 0, which has no answer.