Grade 5 · Unit 1: Number and place value

Written subtraction

Exchange carefully with big numbers and decimals.

Budgets

A school has ৳5 00 000 to build a library. It has spent ৳3 47 850. How much is left? We subtract in columns.

Large numbers

Exchange across the zeros. Or count up: 347 850 → 350 000 → 500 000 = 2150 + 150 000. Both give 152 150.

Decimals

Line up decimal points. Write 15.2 as 15.20. Exchange as normal: 7.35.

Check

Add your answer to the number you subtracted. You should get the starting number. This catches mistakes.

What I learnt

• I can subtract large numbers and decimals in columns.
• I can check by adding.