Addition Equations

A generator of simple addition equations. The unknown x stands for one of the addends and the sum is given, for example 7 + x = 12. Choose the range, up to 5, 10, 20, 100, 1000 or a million. Within 20 and 100 you can also choose three addends, for example x + 5 + 3 = 14, and problems that cross the ten.

On the website you place the equations on a worksheet and add an answer key if you like. They also go on game cards such as memory with the equation and the value of x, or into multiple-choice questions. Every time you generate, you get new equations.

It suits children from Year 2 (1st grade) as missing-number problems, with x in place of the box. Children discover that they find a missing addend by subtracting.