What is doubles plus 1?
Doubles plus 1 is a strategy used to add two consecutive numbers that is, when they are next to each other.
We simply add the smaller number twice or double it and then, add 1 to it, to get the final result.
Here, for example, consecutive numbers 8 and 9 have been added using the doubles plus one strategy.
Here are more examples of the double plus 1 strategy.
Let’s add consecutive soap bubbles,
Adding five and six; there’s no trouble!
Just make the smaller number double,
Then add 1 to the double of the bubbles.
Let's do it!
Have fun with your child by asking them to find the doubles of numbers you say and then use double plus 1 and doubles minus 1 strategies to find the sum of consecutive numbers between 1 and 20.
Related math vocabulary