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Number theory Difficulty 1.0 Junior Find the answer United Kingdom

Hasan writes down a two-digit number. He then writes the same two-digit number next to his original number to form a four-digit number. What is the ratio of his four-digit number to his two-digit number?

(A) $2:1$ (B) $100:1$ (C) $101:1$ (D) $1001:1$ (E) It depends on his number

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