Real-World Examples of Finding the Missing Number in Addition

📚 Quick Study Guide

• ➕ Addition is combining two or more numbers to find their sum.
• ❓ When a number is missing in an addition equation, we can use subtraction to find it.
• 🔑 The basic formula is: Missing Number = Sum - Known Number.
• 💡Remember to always double-check your answer by plugging it back into the original equation.
• 🔢 Example: If $5 + x = 10$, then $x = 10 - 5 = 5$.

✏️ Practice Quiz

1. What number should replace the question mark: $8 + ? = 12$?
   1. 2
   2. 3
   3. 4
   4. 5
2. Sarah has 7 apples. She needs 15 apples in total. How many more apples does she need? $7 + ? = 15$?
   1. 6
   2. 7
   3. 8
   4. 9
3. John has $3. He wants to buy a toy car that costs $8. How much more money does he need? $3 + ? = 8$?
   1. 4
   2. 5
   3. 6
   4. 7
4. What number completes the equation: $? + 6 = 11$?
   1. 3
   2. 4
   3. 5
   4. 6
5. Emily baked some cookies. She gave 4 cookies to her friend and now she has 9 cookies left. How many cookies did she bake originally? $? - 4 = 9$ (Think: ? = 9 + 4)
   1. 11
   2. 12
   3. 13
   4. 14
6. David has some books. He bought 5 more books and now has a total of 13 books. How many books did he have to start with? $? + 5 = 13$?
   1. 6
   2. 7
   3. 8
   4. 9
7. What value of 'x' makes the equation true: $x + 12 = 20$?
   1. 6
   2. 7
   3. 8
   4. 9