Using each of the four digits at the top once, construct an expression that evaluates to an integer between 1 and 20 via any combination of the following operators:

• addition +
• subtraction -
• multiplication *
• division /
• parentheses ()
• Note: operators can be repeated. Ex: 1 + 2 + 3 + 4

Example: Given the digits 1 2 3 4, one possible expression that evaluates to 9 is: 4 * (2 + 1) - 3.

Click on any bar or integer on the Solutions chart to see a list of solutions for that integer.