Tools

Scientific / number

Fraction bars, percents, and circle area — see quantities.

Overview

A fraction relates a whole to its parts. Bar models turn abstract symbols into comparable lengths.

Keep the denominator fixed and change the numerator to stress “how many equal parts are taken.”

Unlike denominators?

This page focuses on meaning; addition with like/unlike denominators has dedicated scenes in the viz catalog.

Is this tool free?

Yes. It runs in the browser with no install.

Good for class demos?

Yes — project it and ask what changes when you drag a parameter.

How do I write the formula afterward?

Open the equation editor or symbol sheet and copy a clean expression.