To divide a decimal by a whole number, use short division and keep the decimal point in line. 8.4 ÷ 4: 8 ÷ 4 = 2, then 4 tenths ÷ 4 = 1 tenth. The answer is 2.1.
To divide by a decimal, change the calculation so you divide by a whole number. Multiply both numbers by 10: 6 ÷ 0.5 becomes 60 ÷ 5 = 12. This works because the answer does not change when both numbers are made ten times bigger.
Worked example
4.8 ÷ 0.6 =
- Multiply both by 10: 48 ÷ 6.
- 48 ÷ 6 = 8.
Answer:8
Key words
- dividend
- the number being divided
- divisor
- the number you divide by
- scale up
- multiply both numbers by the same power of ten
Practise this
New questions every time.
Common Core-referenced: 5.NBT.B.7