Question
Which of the following numbers can be represented as non-terminating repeating decimals?
(a) \( \frac{39}{24} \)
(b) \( \frac{3}{16} \)
(c) \( \frac{3}{11} \)
(d) \( \frac{137}{25} \)
Solution
A rational number \( \frac{p}{q} \) has:
- Terminating decimal if \( q \) has only prime factors 2 and/or 5
- Non-terminating repeating decimal if \( q \) has other prime factors
Option (a): \( \frac{39}{24} = \frac{13}{8} \)
Denominator \( 8 = 2^3 \)
✔ Terminating
Option (b): \( \frac{3}{16} \)
Denominator \( 16 = 2^4 \)
✔ Terminating
Option (c): \( \frac{3}{11} \)
Denominator \( 11 \) (not 2 or 5)
✔ Non-terminating repeating
Option (d): \( \frac{137}{25} \)
Denominator \( 25 = 5^2 \)
✔ Terminating
Final Answer
✔ Correct option: (c) \( \frac{3}{11} \)