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Path: Coding & reasoning evaluation

Find the first invalid reasoning step

Check assumptions, units, calculations, and conclusions in order instead of judging only the final answer.

Starting level
Some basics
Time
25 minutes
Public lesson guide
EN + हिंदी

You will learn to

Locate the first invalid assumption, formula, or inference in a reasoning chain.

Why this matters

Correcting only the final answer hides where the reasoning stopped being reliable.

Three things to remember

  • Check assumptions before arithmetic.
  • Track units and definitions at every step.
  • Separate the first error from later consequences.

See one example

Task

Review a speed calculation.

Weak approach

The final number is wrong.

Stronger approach

Step 3 multiplies distance by time; speed requires division, giving 60 km/h.

Why the stronger approach works

The critique identifies the first error, rule, and corrected result.

Make something yourself

Create a four-step reasoning chain with one error, then annotate its first failure and correction.

A useful starting pointKeep later steps plausible so the first-error check matters.
Practise this lesson

Read further

The source is optional. The complete teaching and practice are available inside AI2Bharat.

Read the primary or official source: OpenAI third-party evaluations