3B

Terminating and recurring decimals

Computing with decimals, converting fractions to terminating or recurring decimals, recurring decimal notation, and rounding.

Two kinds of decimal

A terminating decimal stops: $\tfrac{3}{8} = 0.375$. A recurring decimal repeats forever: $\tfrac{5}{11} = 0.454545\ldots = 0.\overline{45}$.

Example 1●●

Write $\tfrac{5}{6}$ as a decimal.

$5 \div 6 = 0.8333\ldots$
$= 0.8\dot{3}$ (only the $3$ repeats).

Computation

Example 2●

Find $3.2 \times 0.15$ and $4.68 \div 0.12$.

$32 \times 15 = 480$; three decimal places gives $0.480 = 0.48$.
$4.68 \div 0.12 = 468 \div 12 = 39$.
Flashcards
Terminating test
Denominator's prime factors are only 2s and 5s.
$ frac{1}{3}$
$0.\dot{3}$
$ frac{2}{11}$
$0.\overline{18}$
Practice
  1. Find $3.2 \times 0.15$.

  2. Find $4.68 \div 0.12$.

  3. Which fraction gives a recurring decimal?

  4. $\tfrac{5}{6}$ as a decimal is:

  5. Round $0.\overline{27}$ to 3 decimal places.

  6. Write $\tfrac{7}{20}$ as a decimal.

  7. Write $\tfrac{5}{9}$ as a decimal to 3 decimal places.

  8. Find $0.6 \times 4$.

More questions

New numbers every time. Keep going until you get five in a row.

Formula sheet