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UKMT Pink Kangaroo, 2020

Number theory Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

Masha put a multiplication sign between the second and third digits of the number $2020$ and noted that the resulting product $20 \times 20$ was a square number. How many integers between $2010$ and $2099$ (including $2020$ ) have the same property?

(A) $1$ (B) $2$ (C) $3$ (D) $4$ (E) $5$

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