Maths Olympiad Prep

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Number theory Difficulty 5.0 AIME, harder Find the answer

5. What is the least number greater than 1992 that gives a remainder of 77 when divided by 99?

A number or a short expression. Spacing and $ signs are ignored.

Solution

5. Divide 1992 by 9 with a remainder

19929-1992\llcorner 9
1819\frac{18}{-19}
18221\frac{-18}{221}
129\frac{-12}{9}
3

We obtained a remainder of 3. To make the remainder equal to 7, the divisor needs to be increased by four:

1992+4=1996 1992+4=1996 \text {. }

Answer: 1996.

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.