Finding patterns in a multiplication table
About this video
The video uses a partly completed multiplication table to find 6 x 7. It shows that going down the 7s column adds 7 each time, so 6 x 7 is the five fact 5 x 7 = 35 plus one more group of 7, which is 42.
You'll be able to
- use a five fact as a stepping stone to find a six fact.
- explain that each step down a times-table column adds the same number.
- find 6 x 7 = 42 by adding 35 + 7.
Key words
- multiplication table
- A grid that shows the answers to multiplication facts in rows and columns.
- five facts
- Multiplication facts with 5, like 5 x 7 = 35.
- stepping stone
- A fact you already know that helps you reach a new one.
Transcript
- [Narrator] We're told here is a partially completed multiplication table, so we can see the one times tables, then the twos, threes, fours goes all the way to fives, and they want us to solve six times seven. And they tell us, use the five facts. So that's the ones highlighted in purple as a stepping stone, take five groups and add one more group.
So pause this video and have a go at this before we do this together. All right, so we're trying to figure out what six times seven is. So six times seven would be right over here on our multiplication table and they give us a nice hint. Use the five facts as a stepping stone.
Take five groups and add one more group. So what do you mean by that? Well, if you look at this right over here, they tell us that five times seven is 35, five times seven is equal to 35. And if you look at this column here, you can see that you can view this as adding seven every time.
Seven times one is seven, seven times two is 14. Seven times three is 21. Seven times four is 28, seven times five is 35. So every time we're just adding, every time we're just adding seven when you go down this column, so if you wanna figure out what six times seven is or what seven times six is, you just have to add seven more right over here.
So 35 plus seven, we could do that in our head, or we could just write it out over here. Five plus seven is 12, and then 10 plus 30 is 40. We get 42. So six times seven is equal to 42.
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