Number bonds · 20
Number Bonds of 20
10 pairs of numbers from 1 up make 20, including the double 10 + 10. Add 0 and 20 and that's 11.
The pairs that make 20
How to learn the bonds of 20
Each bond of 20 comes from a bond of 10. Since 3 and 7 make 10, 13 and 7 make 20. Two full ten-frames show it: the pair fills one frame and the other frame is already full.
The facts in these bonds
| Add | Turned around | Take away | Take away |
|---|---|---|---|
| 1 + 19 = 20 | 19 + 1 = 20 | 20 − 1 = 19 | 20 − 19 = 1 |
| 2 + 18 = 20 | 18 + 2 = 20 | 20 − 2 = 18 | 20 − 18 = 2 |
| 3 + 17 = 20 | 17 + 3 = 20 | 20 − 3 = 17 | 20 − 17 = 3 |
| 4 + 16 = 20 | 16 + 4 = 20 | 20 − 4 = 16 | 20 − 16 = 4 |
| 5 + 15 = 20 | 15 + 5 = 20 | 20 − 5 = 15 | 20 − 15 = 5 |
| 6 + 14 = 20 | 14 + 6 = 20 | 20 − 6 = 14 | 20 − 14 = 6 |
| 7 + 13 = 20 | 13 + 7 = 20 | 20 − 7 = 13 | 20 − 13 = 7 |
| 8 + 12 = 20 | 12 + 8 = 20 | 20 − 8 = 12 | 20 − 12 = 8 |
| 9 + 11 = 20 | 11 + 9 = 20 | 20 − 9 = 11 | 20 − 11 = 9 |
| 10 + 10 = 20 | same fact | 20 − 10 = 10 | same fact |
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Bonds of 20 FAQ
What are the number bonds of 20?
0 and 20, 1 and 19, 2 and 18, 3 and 17, 4 and 16, 5 and 15, 6 and 14, 7 and 13, 8 and 12, 9 and 11, 10 and 10. Each pair works turned around too.
How many number bonds does 20 have?
11 pairs, counting 0 and 20. The middle pair is a double, 10 and 10, because 20 is even.
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