1. Mental Division – Objectives
Divide by 2, 4, 5 and 10 and give the answer as a decimal.
You may need:
Mini whiteboards
© Hamilton Trust Stepping Up Term Week 10 Day 3

2. £41 £41 Mental Division – Direct Teaching £20.50 £10.25 Half of £41.00
If this was split between 4 children how much would they get each?
£10.25
Half again
£41
Half of £41.00
£20.50
We often need to give answers as decimals when using money…
Ask students to share ideas.
© Hamilton Trust Stepping Up Term Week 10 Day 3

3. Mental Division – Direct Teaching
£41
What if it is split
between 5 children?
£41 ÷ 5 = ? Remember that division is multiplication with holes…
So x 5 = £41
£8 x 5 = £40 start with what you know
£1 what is left?
20p x 5 = £1 don’t forget we’re using money
£41 ÷ 5 =
£8.20
© Hamilton Trust Stepping Up Term Week 10 Day 3

4. £44 ÷ 5 = £8.80 Mental Division – Direct Teaching
Start by dividing £40 by 5 (£8 each).
Then divide the remaining £4 into 5.
£4 is 400 pence so that is 80p each. or
= £8.80
Divide by 10 to get £4.40,
then double to get £8.80.
© Hamilton Trust Stepping Up Term Week 10 Day 3

5. Mental Division – Student Activity
£31 ÷ 4
£34 ÷ 4
Have a go at these with a partner…
Students work on whiteboards or in back of books.
Watch out for students who:
• Do not know their multiplication facts and so can’t make use of them to solve divisions
£31 ÷ 5
£34 ÷ 5
© Hamilton Trust Stepping Up Term Week 10 Day 3

6. Mental Division – Direct Teaching
Discuss in pairs how you would work out each, to give a decimal answer.…
34 ÷ 4
74 ÷ 10
Students discuss in pairs how they would express the answer as a decimal; the next two slides exemplify methodology.
38 ÷ 5
© Hamilton Trust Stepping Up Term Week 10 Day 3

7. Mental Division – Direct Teaching remainder 2, with a divisor of 4
= 8.5
34 ÷ 4
34 ÷ 4 = 8 r2
remainder 2, with a divisor of 4
Students discuss in pairs how they would express the answer as a decimal.
Take feedback, discuss strategies and agree the answer.
Watch out for students who quote the remainder as the decimal, e.g. 34 ÷ 4 = 8.2 rather than 8r2
2/4 is a half, or 0.5
© Hamilton Trust Stepping Up Term Week 10 Day 3

8. Mental Division – Direct Teaching remainder 3, with a divisor of 5
= 7.6
38 ÷ 5
38 ÷ 5 = 7 r3
remainder 3, with a divisor of 5
Students discuss in pairs how they would express the answer as a decimal.
Take feedback, discuss strategies and agree the answer.
Watch out for students who quote the remainder as the decimal, e.g. 38 ÷ 5 = 7.3 rather than 7r3
3/5 is equivalent to 6/10 or 0.6
© Hamilton Trust Stepping Up Term Week 10 Day 3

9. Mental Division - Individual Practice
17 ÷ 4 £21 ÷ 2
35 ÷ 10
39 ÷ 5 £29 ÷ 4
Solve the problems on one of these two boards.
£46 ÷ ÷ 2
£39 ÷ ÷ ÷ 5
The board at the top is a bit easier.
Watch out for students who:
• do not know their multiplication facts and so can’t make use of them to solve divisions;
• try to partition numbers into 10s and 1s to divide (as they would for multiplication), rather than into a multiple of 10 of the divisor and the rest.
Give your answers as decimals.
© Hamilton Trust Stepping Up Term Week 10 Day 3