Grade 2 Number Bonds: Number Bonds to 50

Find the two parts that make 50

What You'll Learn

Find the missing part that makes 50 (37 + ? = 50)
Use tens and ones thinking: make the next ten, then count tens to 50

📖Bonds to 50

Every bond in this lesson makes 50. To find the missing part of 37 + ? = 50, first make the next ten: 37 + 3 = 40. Then count on by tens: 40 + 10 = 50. Together that is 3 + 10 = 13, so 37 + 13 = 50.

Worked examples

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

Example 1
? + 35 = 50
1. A number bond joins two parts to make a whole. The whole is 50 and one part is 35.
2. To find the missing part, take the known part away from the whole: 50 − 35.
3. So the missing part is 15.
Answer: 15
Example 2
11 + ? = 50
1. A number bond joins two parts to make a whole. The whole is 50 and one part is 11.
2. To find the missing part, take the known part away from the whole: 50 − 11.
3. So the missing part is 39.
Answer: 39
Example 3
31 + 19 = ?
1. A number bond joins two parts to make a whole. Here the two parts are 31 and 19.
2. To find the whole, put the parts together: 31 + 19.
3. So the whole is 50.
Answer: 50