Use each of four numbers once to make 24. Build an expression — tap the numbers and signs, or type it.
Building the expression here needs JavaScript. The numbers above are today's puzzle — make 24 using each exactly once. Pencil and paper work fine.
Square any number ending in 5 in your head, with no working, using one multiplication you already know.
Every game, and how long each one takes.
Nothing expires. Yesterday's is still there.