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UKMT Senior Mathematical Challenge, 2022

Algebra Difficulty 1.0 Junior Find the answer United Kingdom

A light-nanosecond is the distance that a photon can travel at the speed of light in one billionth of a second. The speed of light is $3 \times 10^8\,\mathrm{ms}^{-1}$ . How far is a light-nanosecond?

(A) $3\,\text{cm}$ (B) $30\,\text{cm}$ (C) $3\,\text{m}$ (D) $30\,\text{m}$ (E) $300\,\text{m}$

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