The instrument
SOLVE cross-multiplies its way to the missing value, SIMPLIFY runs Euclid's algorithm down to lowest terms, SHARE splits any amount into parts that add back exactly — and the panel beneath the screen writes out every move as it happens.
How to use it
Three modes, one exact core. Sixty seconds from blank page to a fully written proof — here is the whole workflow.
Pick the mode
SOLVE finds a missing value in a proportion, SIMPLIFY reduces a ratio to lowest terms, SHARE splits an amount. The three tabs sit at the top of the instrument.
Feed it what you know
In SOLVE, leave exactly one box blank — that's your unknown. Decimals like 1.5 and fractions like 3/4 both parse exactly; no rounding anywhere in the pipeline.
It solves as you type
There is no equals button. The screen re-solves on every keystroke, and the panel beneath it rewrites the complete proof.
Read it every way
The big line is the answer; the rows below carry the completed proportion, simplest form, unit value, part-to-whole fractions and percentages — repeating decimals overlined, exact.
Copy the working
Every step is written the way a teacher wants it: cross-multiplication lines, Euclid's algorithm, share checks that rebuild the total.
Learn from the chips
One tap on any example chip loads a worked scenario — recipe scaling, map ratios, Pythagorean triples, fair splits.
Questions, answered
The ratio questions that actually come up — short answers, no fluff.