Understand the idea.
Parts that belong together
A number bond shows parts that join to make a whole. Six counters and four counters make ten: . Move one counter from the four to the six. The parts change to seven and three, but none disappear.
Use bonds you know
You can name the same parts in either order: and both make ten. For bigger totals, look for a ten you already have or can make. Two tens together make twenty.
See the method in action.
A bond to ten
What goes with seven to make ten?
Worked solution
- 1
Keep seven as the known part.
The missing part must fill the gap from seven to ten.
- 2
Count on until you reach ten.
Three new counts are needed after seven.
- 3
Check the missing part.
Seven and three join to make the whole ten.
3; 7 + 3 = 10.
A bond to twenty
There are twelve red counters and eight blue counters. How many altogether?
Worked solution
- 1
Split twelve into ten and two.
Keep the first ten together and work with the two extra ones.
- 2
Join the two ones to the eight blue counters.
Those counters make a second group of ten.
- 3
Join the two tens.
Both colour groups are included, giving twenty counters altogether.
20 counters.
Try it yourself.
Check your understanding
What goes with nine to make ten?
Show answer & reasoning
1
Nine needs just one more to reach ten: . The missing part is .
Keep practising
6 worksheet questions
Read the questions online
- Complete: .
- Complete: .
- Complete: .
- Write the same bond in the other order: .
- Complete: .
- Luca says but . Explain the mistake.
Read the worked solutions
- Complete: .
Count on from six: seven, eight, nine, ten.
4 - Complete: .
Sixteen is ten and six.
6 - Complete: .
Eight and two make ten.
10 - Write the same bond in the other order: .
The same parts still make twelve.
. - Complete: .
Nine and one make ten; another ten makes twenty.
11 - Luca says but . Explain the mistake.
The parts are the same; only their order changed.
Both sums are 10.
Curriculum reference & lesson scope
Australian Curriculum v9 and SA Curriculum Mathematics
Year 1 additive situations and number bonds within twenty.
Official curriculum source ↗