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UKMT Grey Kangaroo, 2020

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

The statements on the right give clues to the identity of a four-digit number. What is the last digit of the four-digit number? $4132$ : Two digits are correct but in the wrong places. $9826$ : One digit is correct and in the right place. $5079$ : Two digits are correct with one of them being in the right place and the other one in the wrong place. $2741$ : One digit is correct but in the wrong place. $7642$ : None of the digits is correct.

(A) $0$ (B) $1$ (C) $3$ (D) $5$ (E) $9$

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