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Compare two vendors' yearly cost with the math shown
Practice: Catching mistakes and made-up facts. About 5 minutes.
About this exercise
You're choosing an in-app chat vendor and need to compare yearly costs. Write exactly 2 numbered lines, one per vendor, each showing the math for year-one cost (monthly price x 12 + one-time fees = total), then one final line starting 'Pick:' naming the cheaper vendor, plain text, under 80 words. Use the corrected quote and the expected seat count.
Common mistakes when you ask AI for this
- Asking 'which is cheaper'. The AI gives an answer and a paragraph without the math you can check. Try: Show it: "1. Chatwell: $45 x 12 seats x 12 months + $1,500 = $7,980".
- Trusting the AI to count words. AI is bad at counting. Ask for a total word limit and it often lands over it. Try: Cap each line instead: "each line under 20 words."
- Using the old quote or seats. The $40 price and 10 seats both appear first, with corrections below. Try: Add: "Use 12 seats and Talkbox's corrected $50 price."
- Verdict before numbers. The AI opens with its pick and adds feature opinions. Try: Add: "Pick line last, after both totals. Cost only. Plain text."
What a strong prompt includes
- Asks to show the math
- Uses the corrections
- Puts the pick last
- Decides on cost only
- Sets a word limit
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