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\ 03-Oct-2025 Bharat Arora Proof-9 Reader’s Sign _______________________ Date __________

Subtracting a 1-digit number from a 2-digit number

Arshi collected 18 shells. 7 of them broke. How many shells are left with her?

To know the number of shells left, let us subtract 7 from 18.
Step 1. Write the bigger number above Step 2. Subtract the tens next.

and the smaller number below. Tens Ones

Subtract the ones first. 1 8
– 7
1 1
Tens Ones
1 8
– 7 There is no tens in the second
1 number to subtract.
So, write 1 in the tens place.

8 ones – 7 ones = 1 one Hence, 18 – 7 = 11.

Write 1 in the ones place. Thus, 11 shells are left with Arshi.

Some more examples.

(a) (b) (b)
Tens Ones Tens Ones Tens Ones
1 3 1 8 1 6
– 2 – 5 – 6
1 1 1 3 1 0

Challenge Question Critical Thinking
If 18 − 7 = 11, can you create another subtraction fact using these same
numbers, but in a different order?

Practice time 4F

Subtract the following.
1. Tens Ones 2. Tens Ones 3. Tens Ones 4. Tens Ones

1 2 1 9 1 4 1 5
– 2 – 7 – 3 – 4

5. Tens Ones 6. Tens Ones 7. Tens Ones 8. Tens Ones
1 7 1 1 1 6 1 8
– 5 – 1 – 2 – 6

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