Target number
Make the target from four numbers, each used once, with + − × ÷ and brackets.
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How it works
Every target has at least one solution, found by a solver before the question is shown. Any expression that uses all four numbers once and makes the target is right, and it submits itself. Type x or * for times and / or : for divide.
A sample question
Make from , each once, with + − × ÷ and brackets.