Real Agent Cases

Catch a wrong multiplication answer from ChatGPT while checking homework

Posted
by Treehouse Dad (@treehousedad)
Last checked
Method:
How we verify

Evidence: Screenshots or logsThe source shows screenshots, a transcript or the agent's output.

FailureThe source says the agent did not get the job done.

What went wrong: ChatGPT gave a wrong answer to a simple multiplication; the poster caught it with a calculator.

Outcome

Helping their son with homework, the poster had ChatGPT (GPT-5) do a simple multiplication problem. They couldn't reproduce its answer, checked with a calculator, and found ChatGPT was wrong.

Agent

ChatGPT

Prompt Recreated prompt

The source didn't share its exact prompt, so we wrote this from what it describes.

Run this task now, exactly as written below. Everything you need is here, so start straight away and only stop if something required is missing or a rule below tells you to.

Goal: Help me check my child's math homework, showing your working so I can verify every answer.

Fill in before running:
- The problems: [PROBLEMS]
- My child's answers: [ANSWERS]

Rules:
- Show each step of the calculation, not just the final answer.
- Say clearly which of my child's answers match and which don't.
- For any arithmetic, tell me to confirm the result with a calculator.
- Explain mistakes in a way a child can follow.
- Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify.

Output: A line-by-line check with working, and a short note on any mistakes.

You'll know it worked when: every answer is confirmed by the working and a calculator.

Try this in:

This prompt has blanks to fill in, like [PROBLEMS]. We'll copy it instead of filling it in, so you can edit it before you send.

Opens in a new tab. We don't see what you send.

These links are only a shortcut. We're not affiliated with OpenAI, Google or xAI, and your results may not match the source.

Optional stronger version

Our rewrite with extra checks. The poster didn't test it.

Run this task now, exactly as written below. Everything you need is here, so start straight away and only stop if something required is missing or a rule below tells you to.

Goal: Help me check my child's math homework, showing your working so I can verify every answer.

Fill in before running:
- The problems: [PROBLEMS]
- My child's answers: [ANSWERS]

Rules:
- Show each step of the calculation, not just the final answer.
- Say clearly which of my child's answers match and which don't.
- For any arithmetic, tell me to confirm the result with a calculator.
- Explain mistakes in a way a child can follow.
- Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify.
- If you're unsure of any result, say so instead of giving a confident number.

Output: A line-by-line check with working, and a short note on any mistakes.

You'll know it worked when: every answer is confirmed by the working and a calculator.

Before you finish: re-read my goal and constraints, check your answer against each one, and list anything you assumed or couldn't confirm.

Source

https://x.com/treehousedad/status/1960402697993249262

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