# Missing Number in Subtraction

The basic concept of finding the missing number in subtraction sums with one-digit number. These give us support and idea about the basic subtraction facts, as well as help us to understand the subtraction's relationship to addition. It also assists as an introduction to learning algebra (as the missing number could be represented by a variable or a letter). While solving the subtraction problems children will complete the missing number to find the correct calculation. Now we will learn how to find missing number in subtraction.

What is the missing number in these subtraction sums?

(i) 9 ? = 4

What number taken away from 9 leaves 4? The answer is 5.
Therefore, the sum should be written 9 – 5 = 4

(ii) ? 2 = 5

From what number must you subtract 2 so as to leave 5? The answer is 7. Therefore, the sum should be written 7 – 2 = 5

(iii) 6 - ? = 5

What number taken away from 6 leaves 5? The answer is 1.
Therefore, the sum should be written 6 – 1 = 5.

(iv) ? 7 = 1

From what number must you subtract 7 so as to leave 1? The answer is 8. Therefore, the sum should be written 8 – 7 = 1