Topic 5 of 10 · Method 2: subtract large chunks
Chunking
Mr Boston
Chunking is a friendly method when big numbers feel scary. Instead of dividing all at once, we keep taking away big, easy chunks.
Method 2 – Chunking
Instead of dividing all at once, subtract large chunks.
156 ÷ 12
12 × 10 = 120
156 − 120 = 36
12 × 3 = 36
36 − 36 = 0
10 + 3 = 13
Answer = 13
156 is made of 10 twelves and 3 twelves. 10 + 3 = 13 twelves.
Good chunks to use
Easy chunks are × 10, × 5, × 2 and × 1. For bigger numbers, try × 100 or × 20. For 12 that means:
12 × 1 = 1212 × 2 = 2412 × 5 = 6012 × 10 = 12012 × 20 = 240
- Take away the biggest chunk that fits.
- Keep going until what is left is smaller than the number you are dividing by.
- Add up how many lots you took away. That’s your answer. Anything left over is the remainder.
Tayo
You don’t have to pick the perfect chunk. A smaller chunk just means a few more steps, and you still get there!
Practise
Quiz: earn your stamp
Printable worksheet
Chunking worksheet. The questions are on the first page, and the answers for grown-ups are on the last page, so you can print just the first page for your child.
Printing is optional. A4 size.