The idea, step by step
Every group is a pair
A pair has 2 objects. The twos facts count pairs: one pair has 2, two pairs have 4, three pairs have 6. The totals are even numbers because all objects have a partner.
Build from a known fact
If 5 pairs make 10, then 6 pairs make 12: add one more pair. A fact such as 2 × 7 can also mean double 7. Show or explain the groups as well as remembering the fact.
| Pairs | 1 | 2 | 3 | 4 | 5 | 6 |
|---|---|---|---|---|---|---|
| Objects | 2 | 4 | 6 | 8 | 10 | 12 |
A common trap
Adding 2 only once for a story with several pairs.
Instead: Count one group of 2 for each pair. Four pairs mean four groups of 2.
See the thinking
Count seven pairs
There are 7 bicycles with 2 wheels each. How many wheels?
- Five bicycles have 10 wheels.
- Two more bicycles add 4 wheels; 10 + 4 = 14.
Use a known fact
You know 8 pairs make 16. How many objects are in 9 pairs?
- Nine pairs are one more pair than eight pairs.
- 16 + 2 = 18.
Check your understanding
Find 2 × 6.
Show answer
12
Double 6 is 12, or count six groups of two.
Your turn
6 questions · Work at your own pace.
Read the questions online
- Find 2 × 3.
- Find 2 × 5.
- Find 2 × 8.
- Ten children each need 2 gloves. How many gloves?
- There are 12 shoes arranged in pairs. How many pairs?
- Explain how 2 × 4 helps you find 2 × 5.
Read the worked solutions
- Find 2 × 3.
2 + 2 + 2 = 6.
6 - Find 2 × 5.
Five pairs contain 10 objects.
10 - Find 2 × 8.
Double 8 is 16.
16 - Ten children each need 2 gloves. How many gloves?
Ten groups of 2 make 20.
20 gloves. - There are 12 shoes arranged in pairs. How many pairs?
6 groups of 2 make 12.
6 pairs. - Explain how 2 × 4 helps you find 2 × 5.
The fifth group adds 2 to the total.
2 × 4 = 8; add one more pair to get 10.
Curriculum reference & lesson scope
Australian Curriculum v9 and SA Curriculum Mathematics
Equal groups; arrays; repeated addition; sharing/grouping; twos facts; doubling and halving.
Official curriculum source ↗