🕵️ Missing Number Mystery
Find the missing number in addition, subtraction, multiplication and division number sentences.
How to play
One number in each number sentence has been replaced by a box. Use the other numbers and the operation to work out what must go in the box, then type it in. Reversing the operation often helps.
⌨️ Keyboard: press 1–4 to pick an answer, or type your answer and press Enter.
What it teaches
Solving for an unknown in a number sentence is early algebra. It appears from Year 2 (missing addends) through Year 6, and builds the understanding students need for equations in Year 7.
Levels: Addition (Add within 10) · Add & subtract (Within 40) · All four (× and ÷ too)
Free to play, with no sign-up and no ads beside the game. Best scores are saved only in this browser. All artwork and sounds are made in code by makekite.