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Addition within ten

You learn to add to ten faster by starting at the bigger number.

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How to work it out

  1. Put the larger number in your head.
  2. Count on the smaller number in ones.

A worked example

2 + 6

  1. Start at 6.
  2. Count on 2: 7, 8.
  3. So 2 + 6 = 8.
More examples

3 + 5

  1. Start at 5.
  2. Count on 3: 6, 7, 8.
  3. So 3 + 5 = 8.

4 + 4

  1. Both numbers are the same, so start at 4.
  2. Count on 4: 5, 6, 7, 8.
  3. So 4 + 4 = 8.

Try it yourself

  1. 2 + 3 =

  2. 2 + 7 =

Watch out

  • You start at the first number and count a long way: for 2 + 7 you count on seven.

    First look which number is bigger. Start there, so you only have to count a few.

  • You count the number you start at as well: for 6 + 2 you say 6, 7 and get 7.

    Keep 6 in your head and start counting at 7.

Tips

  • You can swap an addition round, so choose the way with the least counting.
  • Keep the big number in your head and count the small number on your fingers.

Exceptions

  • You cannot swap a subtraction round: always start at the first number.

Why it works

For 2 + 6 you can count on 6 from 2, but you can also count on 2 from 6. The second way is shorter, and you are less likely to make a counting mistake. You can swap the numbers in an addition: 2 + 6 and 6 + 2 are the same.