About Equation Builder
A target number and four small numbers. Use all four numbers and any operators (+, −, ×, ÷, parentheses) to make the target. There are usually multiple solutions. Find one.
How to Play
- See the target number at the top
- Tap each of the 4 small numbers and operators in sequence to build an expression
- Use parentheses for order of operations
- Each number must be used EXACTLY once
- Tap Check to verify
Tips & Strategy
- Try addition/subtraction combinations first — fastest to evaluate
- Multiplication shortcuts: if target is large, multiplication is probably involved
- Parentheses unlock harder targets: (a + b) × c is very different from a + b × c
- If stuck, try working backward from the target
Brain Benefits
Equation Builder trains arithmetic flexibility — the ability to manipulate numbers in multiple ways to reach a goal. This skill underlies algebra, mental math, and quantitative reasoning generally.