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UKMT Senior Mathematical Challenge, 2020

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

The letters $p$ , $q$ , $r$ , $s$ and $t$ represent different positive single-digit numbers such that $p - q = r$ and $r - s = t$ . How many different values could $t$ have?

(A) $6$ (B) $5$ (C) $4$ (D) $3$ (E) $2$

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