Adding and taking away within 18 · Usually met around P1
Near doubles
One apart: double, then add 1.
How to do it
Method
One apart: double, then add 1
6 + 7 = 6 + 6 + 1 = 13
Another way
Make ten
7 + 3 = 10, 10 + 3 = 13
In full
6 + 7 isn't a new fact. It's 6 + 6 = 12, plus one more: 13. Any two numbers that are one apart can lean on a double you already know. For one-digit sums past ten, you can also make ten instead: 6 + 7 → 7 + 3 = 10, 10 + 3 = 13.
Worked examples
Have a go first, then open each one for the answer and the working.
Example 1
4 + 3
Show the answer and working
Answer: 4 + 3 = 7
The numbers are one apart, so double and add one: 3 + 3 = 6, 6 + 1 = 7
Example 2
5 + 4
Show the answer and working
Answer: 5 + 4 = 9
The numbers are one apart, so double and add one: 4 + 4 = 8, 8 + 1 = 9
Example 3
3 + 2
Show the answer and working
Answer: 3 + 2 = 5
The numbers are one apart, so double and add one: 2 + 2 = 4, 4 + 1 = 5
Practise it in the game →Adding and taking away within 18 · Free to start, unlimited questions, no download