Fineuralab

Start with logic and statistics. Practice reasoning, make sense of numbers, and bring what you learn to your own research and projects.

From 20% to 30%: what is the relative increase?

An AI answer says ‘a 10% increase’. Calculate it yourself before deciding how to revise it.

Choose your answer

Show the calculation

The increase is 10 percentage points. Relative growth divides by the starting rate: (30% − 20%) ÷ 20% = 50%.

Practice percentages and percentage points →
A quick exercise. Answers are not saved or counted toward course progress.

What would you conclude?

Wrong percentage, yet a score of 82?

A deliberately wrong explanation of a change from 20% to 30% scored 82 in the English demo and 73 in Chinese. The rules rewarded structure and signals without checking the arithmetic. Read the inputs, outputs and calculation, then rerun them.

Open the case and checker

Projects you can open

View all projects and their standards

Two-person review has not started

Twenty synthetic fixtures and a local review workbench are ready. There is no human agreement result. The tool cases above are executed software tests, not conclusions from two reviewers.

View calibration material · Research notes and methods

This is a one-person site

I maintain Fineuralab on my own. Some pages are finished tools, some are methods I currently use, and some are experiment designs that have not run yet. I label them for what they are instead of presenting every page as a result. If you find a factual error, broken source, or unclear boundary, email me directly.