burger fun / Four Fours / Solver
Make 73 with four 4s
The classic four fours puzzle: build an expression from exactly four 4s that equals 73. 73 cannot be made from four 4s at all under these rules — tiers 1 and 2 are proven exhaustively, and the bounded tier-3 search came up empty too.
Solutions using only + - × ÷
No expression made of four plain 4s and + - × ÷ reaches 73 — the solver checked every possible expression.
Solutions with concatenation and decimals
Concatenation and decimals do not help for 73 either — every combination was checked.
Solutions with square roots, factorials, exponents
No solution found at this tier within the solver’s search bounds — square roots, factorials, and exponents all come up empty.
Zero solutions found. Not for lack of trying — the solver tried everything its rules allow.
How 73 compares
73 is one of only 5 targets out of 100 that four 4s cannot reach — the full list is 73, 77, 87, 93, 99. Next door, 72 has 178 solutions and 74 has 10 solutions.
The nearest fellow holdout is 77, also proven impossible.
Make 72 with four 4s · Make 74 with four 4s
The Number Lab
Same idea, different constraints: four 9s, four 4s, or any four digits you like.
- Four Nines — the daily puzzle
- Four Nines solver — every target, solved
- Four Fours — the 1881 original
- Four Fours solver — including the impossible five
- Make 24 solver — any four digits
- Today's 24 — one new hand a day
Got what you came for?
Stay for something you did not search for.
- Four Nines — the daily sibling: four 9s, one target, new at midnight
- The Reflex Lab — nine ways to measure your hands and memory, none of them polite about it
- hand me something weird — a random pick from the directory. Could be the horse.
Read up on the 1881 original, pick another number in the solver, or find more free math games.