Grade 2 · Unit 1: Number and place value

Subtracting on paper

What if there are not enough ones?

Saving money

Rima has ৳65 in her money box. She spends ৳23. How much is left? We can subtract on paper.

Ones first, then tens

Write the bigger number on top. Subtract the ones: 5 − 3 = 2. Subtract the tens: 6 − 2 = 4. The answer is 42.

Exchanging a ten

2 − 7: there are not enough ones! Exchange 1 ten for 10 ones. Now we have 4 tens and 12 ones. 12 − 7 = 5 and 4 − 2 = 2. The answer is 25.

Check with addition

Addition is the inverse of subtraction. Check: 25 + 27 = 52 ✓ Always check your answer this way.

What I learnt

• I can subtract 2-digit numbers in columns.
• I can exchange a ten for ten ones.
• I can check by adding.