MathDB
Boxing Match

Source: 2016 AIME II #4

March 17, 2016
AMCAIMEAIME IIBernie Sanders

Problem Statement

An a×b×ca\times b\times c rectangular box is built from abca\cdot b \cdot c unit cubes. Each unit cube is colored red, green, or yellow. Each of the aa layers of size 1×b×c1\times b \times c parallel to the (b×c)(b\times c)-faces of the box contains exactly 99 red cubes, exactly 12 green cubes, and some yellow cubes. Each of the bb layers of size a×1×ca\times 1 \times c parallel to the (a×c)(a\times c)-faces of the box contains exactly 20 green cubes, exactly 25 yellow cubes, and some red cubes. Find the smallest possible volume of the box.