Question

Explain why you would make one of the addends a tens number when solving an addition problem.

Answer 1

Addends are numbers used in addition problems, they refers to the numbers that are added together. Addition problems can have two or more addends which can be positive or negative and they can be single digit or double digits.
When solving addition problems, it is advisable to make one of the addends a tens number because, it makes the addition operation easier to manipulate.

Answer 2

Since we can add a number to a tens number easily, we make one of the addends a tens number when solving an addition problem.

Example 1:

Add 9 and 6.

9 + 6 = 9 + (1 + 5)

        = (9 + 1) + 5

        = 10 + 5 = 15

Note that adding 10 and 5 is much easier than adding 9 and 6.

Example 2:

Add 18 and 16.

18 + 16 = 18 + (2 + 14)

        = (18 + 2) + 14

        = 20 + 14 = 34

Note that adding 20 and 14 is much easier than adding 18 and 16.