Stage 8 · Fractions & decimals
Dividing decimals
Make the divisor whole: move both points.
How to do it
Method
Make the divisor whole: move both points
4.8 ÷ 0.6 = 48 ÷ 6 = 8
Another way
Long division
7.2 ÷ 4 = 1.8, the points lined up
In full
÷ 0.1, 0.01 and 0.001 move the point one, two and three places to the right, the same as × 10, 100 and 1000: 3.25 ÷ 0.01 = 3.25 × 100 = 325. A decimal ÷ a whole number: divide as whole numbers, then put the point back where it was: 7.2 ÷ 4 → 72 ÷ 4 = 18 → 1.8. Dividing by a decimal: move the point in both numbers the same number of places to the right until the divisor is whole; the answer doesn't change: 4.8 ÷ 0.6 = 48 ÷ 6 = 8; 6 ÷ 0.4 = 60 ÷ 4 = 15, filling in a zero. Long division works too: it also makes the divisor whole first and lines the answer's point up with the dividend's — the same answer.
Worked examples
Have a go first, then open each one for the answer and the working.
Example 1
2.4 ÷ 4
Show the answer and working
Answer: 2.4 ÷ 4 = 0.6
2.4 ÷ 4: divide as whole numbers, 24 ÷ 4 = 6, then put the point back one place → 0.6
Example 2
81.9 ÷ 9
Show the answer and working
Answer: 81.9 ÷ 9 = 9.1
81.9 ÷ 9: divide as whole numbers, 819 ÷ 9 = 91, then put the point back one place → 9.1
Example 3
92 ÷ 0.1
Show the answer and working
Answer: 92 ÷ 0.1 = 920
92 ÷ 0.1: ÷ 0.1 moves the point one place right, the same as × 10: 92 × 10 = 920
Example 4
67 ÷ 0.001
Show the answer and working
Answer: 67 ÷ 0.001 = 67000
67 ÷ 0.001: ÷ 0.001 moves the point three places right, the same as × 1000: 67 × 1000 = 67000
Practise dividing decimals in the game →Stage 8 · Fractions & decimals · Free to start, unlimited questions, no download