burger fun / Four Fours / Solver
Make 37 with four 4s
The classic four fours puzzle: build an expression from exactly four 4s that equals 37. 37 cannot be made with + - × ÷, concatenation, or decimals (the solver checked every expression) — solutions need square roots, factorials, or exponents.
Solutions using only + - × ÷
No expression made of four plain 4s and + - × ÷ reaches 37 — the solver checked every possible expression.
Solutions with concatenation and decimals
Concatenation and decimals do not help for 37 either — every combination was checked.
Solutions with square roots, factorials, exponents
(.4 + 4!) / .4 - 4! = 37(4! + sqrt(4)) / sqrt(4) + 4! = 37
2 distinct solutions found in total, after removing trivial rearrangements.
Make 36 with four 4s · Make 38 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
Read up on the 1881 original, pick another number in the solver, or find more free math games.