Dividing by a one-digit number · Usually met around P3
Dividing tens and hundreds by one digit
Divide the number of tens, then put the 0 back.
How to do it
Method
Divide the number of tens, then put the 0 back
60 ÷ 3: 6 tens ÷ 3 = 2 tens = 20
Another way
Think of multiplying
3 × 20 = 60 → 60 ÷ 3 = 20
In full
A whole number of tens is so many tens: 60 is 6 tens. 60 ÷ 3 shares 6 tens equally into 3, 2 tens each, that is 20. So work out 6 ÷ 3 = 2 from the division facts, then put the 0 back on the end. Hundreds work the same way: 600 ÷ 3 shares 6 hundreds into 3, 2 hundreds each, that is 200. More than 9 tens is fine too: 120 ÷ 4 shares 12 tens into 4, 3 tens each, that is 30. A two-digit number can be split into tens and ones and each divided: 84 ÷ 4 → 80 ÷ 4 = 20, 4 ÷ 4 = 1, 20 + 1 = 21. Or think of multiplying, to find it and to check: 3 × 20 = 60, so 60 ÷ 3 = 20.
Worked examples
Have a go first, then open each one for the answer and the working.
Example 1
4500 ÷ 5 = □
Show the answer and working
Answer: 900
4500 is 45 hundreds: 45 ÷ 5 = 9, then two 0s, 900.
Example 2
630 ÷ 7 = 9
True or false?
Show the answer and working
Answer: False
630 ÷ 7 = 90. Check: 7 × 90 = 630.
Example 3
810 ÷ □ = 90
Show the answer and working
Answer: 9
Think of multiplying: □ × 90 = 810, so □ is 9.
Practise it in the game →Dividing by a one-digit number · Free to start, unlimited questions, no download