Week 06 · Two steps and patterns
Wednesday
Patterns in the times table
// Solve, estimate and look for patterns
⏱ about 15 min
Wednesday: Patterns in the times table
Oliver unrolls a long chart of times facts on a flat rock.
"I have noticed something curious," he says.
"Every product of 4 is an even number."
"Why should that be?"
Bennie thinks for a moment.
"Four of something is two of it, plus two more of it."
"Two equal parts always make an even number."
Learn it: why 4 times a number is even
4 × 7 is the same as 2 × 7 + 2 × 7.
2 × 7 = 14, and 14 + 14 = 28.
A number made of two equal parts is even.
So 4 times any whole number is even.
Look at 4 rows of 7. The top two rows match the bottom two rows.
EVEN OR ODD?
- Read the question.
- Tap your answer.
Is 4 × 7 even or odd?
Is 3 × 5 even or odd?
Is 6 × 9 even or odd?
Is 7 × 7 even or odd?
Is 8 × 3 even or odd?
More patterns
The products of 5 always end in 0 or 5.
In the 9s, the tens digit goes up by 1.
At the same time, the ones digit goes down by 1.
9 × 2 = 18, 9 × 3 = 27, 9 × 4 = 36.
WHAT COMES NEXT?
- Read the question.
- Tap your answer.
6, 12, 18, 24, ? What comes next?
9, 18, 27, 36, ? What comes next?
8, 16, 24, 32, ? What comes next?
7, 14, 21, 28, ? What comes next?
50, 55, 60, 65, ? What comes next?
SPOT THE PATTERN
- Read the question.
- Tap your answer.
Which number could be a product of 5?
In 9 × 7 = 63, the digits 6 and 3 add up to what?
Which product is odd?
2 × 8 is the same as which sum?
Test each pattern with a few facts.
| Pattern | True or false? |
|---|---|
| 4 times any number is even. | ? |
| Every product of 5 ends in 5. | ? |
| Odd times odd is odd. | ? |
| 6 × 3 is the same as 3 × 6. | ? |
WHY THIS EXERCISE5 × 2 = 10, which ends in 0, not 5.
Try it
Write the 4s facts from 4 × 1 to 4 × 10 on paper.
Circle every even product.
What do you notice?
Circle every even product.
What do you notice?
Draw 4 rows of 6 dots. Show the two equal halves.
Clever noticing! Tomorrow Chris tells a story about Oliver.