Addition

Front

What is addition?

Back

Addition is a mathematical operation that combines two or more numbers to get a total or sum.

Front

What is the sum of 2 and 9?

Back

The sum of 2 and 9 is 11.

Front

What is the sum of 5 and 7?

Back

The sum of 5 and 7 is 12.

Front

What is the sum of 5 and 10?

Back

The sum of 5 and 10 is 15.

Front

What is the sum of 3 and 10?

Back

The sum of 3 and 10 is 13.

Front

What is the sum of 7 and 1?

Back

The sum of 7 and 1 is 8.

Front

What is the commutative property of addition?

Back

The commutative property of addition states that changing the order of the addends does not change the sum (e.g., a + b = b + a).

Front

What is the associative property of addition?

Back

The associative property of addition states that the way in which numbers are grouped does not change their sum (e.g., (a + b) + c = a + (b + c)).

Front

What is the identity property of addition?

Back

The identity property of addition states that the sum of any number and zero is that number (e.g., a + 0 = a).

Front

How do you add two-digit numbers?

Back

To add two-digit numbers, align the numbers by place value, add the digits in the ones place, carry over if necessary, and then add the digits in the tens place.