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UKMT Junior Mathematical Challenge, 2024

Number theory Difficulty 1.0 Junior Find the answer United Kingdom

The world's smallest vertebrate is much shorter than its name! Discovered in 2022, the frog paedophryne amauensis is only 7.7 mm long. Approximately how many of these frogs, placed end to end, would be needed to make a line 1 metre long?

(A) $100$ (B) $130$ (C) $260$ (D) $390$ (E) $520$

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