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UKMT Senior Mathematical Challenge, 2022

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

In 2021, a first class postage stamp cost 85p and a second class postage stamp cost 66p. In order to spend an exact number of pounds and to buy at least one of each type, what is the smallest total number of stamps that should be purchased?

(A) $10$ (B) $8$ (C) $7$ (D) $5$ (E) $2$

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