31
It is: (-31+87)+3 = 59
31
Halloween is October 31
31
They are three terms of an expression that can be simplified to: 3p -31
31%
It is: 5x+31
You can invent infinitely many expressions that have a value of 31, for example: 31 31 + 0 31 + 0 + 0 30 + 1 30 + 1 + 1 1 x 31 5 x 6 + 1 etc.
31-3d
They are three terms of an expression that can be simplified to: 3p -31
31 plus n