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Compare two phone plans by the cost of a full year

  • For High school students
  • You practice Showing an example of what you want
  • Time about 5 minutes

About this exercise

You're paying for your own phone plan now and found two prepaid options. Compare the full cost of 12 months, including any one-time fee and the sale price. Get exactly 3 numbered lines in plain text, under 70 words: 1. Plan A's 12-month cost with the math; 2. Plan B's, same shape; 3. which is cheaper and by how much. No tips. Write a prompt that gets you exactly that.

Common mistakes when you ask AI for this

  • Missing the fine print. The AI uses the 3-month sale from the headline. Try: Add: "Use the fine print: sale for 2 months only."
  • Comparing monthly prices. The AI compares $25 and $30 and ignores the fee and sale. Try: Say: "Compare 12 months, with the fee and the sale."
  • No math shown. The AI gives totals without the working. Try: Show it: "1. Plan A: $25 x 12 = $300 + $15 fee = $315".
  • Getting tips. The AI echoes your friend about unlimited data. Try: Add: "No tips. Line 3 only says which is cheaper."
  • Trusting the AI to count words. AI is bad at counting. Ask for "under 70 words" and it often lands well over. Try: Cap each part: "each line under 16 words."

What a strong prompt includes

  • Uses the fine print
  • Compares a full year
  • Shows the math
  • Sets the number of lines
  • Sets a word limit

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