Missing Numbers - Version 1.0 Improve your basic arithmetic skills by finding the missing number/s in the operation displayed or by playing the missing numbers game. You can select any or all of the operations to ask from, set time limit, and enter answers from keyboard or from multiple choice answers. To improve your basic multiplication and addition skills you can play the missing numbers game with numbers 1 to 10. Find out each number in the table which is formed by multiplication or addition of the numbers selected.