Doubles and Near Doubles

Front

What is a double in addition?

Back

A double in addition refers to adding a number to itself, such as 7 + 7.

Front

What is the result of doubling the number 5?

Back

The result of doubling the number 5 is 10 (5 + 5).

Front

What is a near double in addition?

Back

A near double is when you add a number to a number that is one more or one less than its double, such as 8 + 9 (which is near double of 8 + 8).

Front

Calculate 8 + 9 using the near double strategy.

Back

8 + 9 can be calculated as 8 + 8 + 1, which equals 17.

Front

What is the sum of 9 + 9?

Back

The sum of 9 + 9 is 18.

Front

How can you use doubles to solve 2 + 8?

Back

You can use doubles by recognizing that 2 + 8 is the same as 2 + 2 + 6, where 2 + 2 = 4 and then adding 6 gives 10.

Front

What is the sum of 7 + 7?

Back

The sum of 7 + 7 is 14.

Front

If 5 + 5 = 10, what is the double of 5?

Back

The double of 5 is 10.

Front

How can you express 8 + 9 using doubles?

Back

You can express 8 + 9 as 8 + 8 + 1, where 8 + 8 = 16 and then adding 1 gives 17.

Front

What is the relationship between doubles and near doubles?

Back

Doubles are exact sums of a number added to itself, while near doubles are sums that are close to doubles, typically involving an additional 1.