The Universal Calculation Engine
Insights
The Universal Calculation Engine

Label knowns and unknowns in words first

Part of: Word Problems

Steps for word problems: write what you know, what you want, then simplify or solve.

The steps

Use the same order each time so when an answer is wrong, you know which step to re-check. Word Problems shows the whole topic in one place.

Why one line at a time

One algebraic move per line. If you combine two moves on one line and get stuck, you cannot see which move was wrong.

Worked pattern

Example: balance an equation—add or subtract on both sides, or multiply or divide both sides by the same nonzero number. Write the new equation on the next line each time.

Two ways to write work

One step per line
Two steps on one line

Confirm

Core lesson

Go deeper: Word Problems. Use the calculators below with your own loan or bill numbers, not only the examples on this page.

Use the calculator

FAQ

Where is the main lesson?

Word Problems has the full topic, examples, and practice links.

Which calculator first?

After your setup is on paper, open Percentage for a quick numeric pass.