Four Fours

Beremiz shows how to make each of the numbers from zero to ten by combining exactly four 4s.

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Brazil 4 maths – The Definitive Four Fours Answer Key

Four fours is a mathematical puzzle. The goal of four fours is to find the simplest mathematical expression for every whole number from 0 to some maximum, using only common mathematical symbols and the digit four (no other digit is allowed).