Use near doubles

Near-doubles reasoning identifies two addends that differ by one and relates their sum to a known double: for example, 6 + 7 can be found from 6 + 6 by adding one. Within sums to 20, this relationship supports efficient mental addition and helps connect addition facts with related subtraction facts, without extending to larger numbers or generalized algebraic rules.

Detailed Explanation: Use near doubles

Near doubles are two numbers that are next to each other, such as $6$ and $7$ . Start with the easier double, then add $1$ .

Example:

6+7

Notice that $7$ is one more than $6$ .
Think of the double $(6+6)$ :

6+6=12

Add the extra $1$ :

12+1=13

So,

6+7=13

You can also think of it as $(7+7=14)$ , then take away $1$ , which also gives $(13)$ .

Learn by doing: Use near doubles

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Addition - Whole Number - Near Doubles - Column

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Use near doubles

Detailed Explanation: Use near doubles

Learn by doing: Use near doubles

Practice with unlimited practice problems

Practice:

Addition - Whole Number - Near Doubles - Column