Grade 2 Number Bonds: Number Bonds to 20

Worked examples

Real problems from the practice worksheets, solved one step at a time.

1. Example 1

   ? + 7 = 9

   1. A number bond joins two parts to make a whole. The whole is 9 and one part is 7.
   2. To find the missing part, take the known part away from the whole: 9 − 7.
   3. So the missing part is 2.

   Answer: 2

2. Example 2

   13 + 3 = ?

   1. A number bond joins two parts to make a whole. Here the two parts are 13 and 3.
   2. To find the whole, put the parts together: 13 + 3.
   3. So the whole is 16.

   Answer: 16

3. Example 3

   9 + ? = 20

   1. A number bond joins two parts to make a whole. The whole is 20 and one part is 9.
   2. To find the missing part, take the known part away from the whole: 20 − 9.
   3. So the missing part is 11.

   Answer: 11