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Equation Detective Puzzle

Equation Detective

Equation Detective is a logic puzzle where you infer who bought what, when, and for how much by translating verbal clues into simple equations and inequalities. You fill in a grid of people, items, days, and prices to crack the case.

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Examples of Equation Detective

Solve Equation Detective Puzzle

Equation Detective is a logic grid puzzle: you translate verbal clues into algebraic or relational statements, then fill out a matrix of people, items, days, and prices.

1. Find Definite Answers
  • Work through the clues identifying the ones where you can easily input an answer in the grid.
  • Tick off clues as you go.

2. Use Elimination to Fill In
  • Whenever you place an answer in a row, check to see if any further answers are now achievable.
  • Combine clues: if “Cookie cost £2 more than juice” and you know Juice = £3, deduce Cookie = £5, then mark those.

3. Leave Hard Clues Till End
  • Once you have resolved the easy answers, move onto the harder ones, as often the existing answers can help you with the harder clues.

Pro Tips
  • Use a pencil for any matches you are not sure of.
  • Work systematically: handle all definitive positive clues first, then fill in others.
  • Re-read each clue after filling part of the grid – you’ll often uncover implicit deductions you missed initially.

Example Equation Detective Puzzle

Problem:
Three students – Jake, Layla, and Emma – each bought one item from the school tuck shop (crisps, cookie, juice) on a different day (Monday, Wednesday, Friday).

Each item cost a different amount, and the clues below reveal what happened.
Clues:
1. The cookie cost £2 more than the juice.
2. The crisps cost £1 less than the cookie.
3. Jake did not buy anything on Friday.
4. The person who bought the crisps paid £3.
5. Layla bought her item on Wednesday.
6. Emma paid £4.
7. The juice was not purchased on Wednesday.

Solution Grid:
Preson Day of Week Product Price
Jake Monday Juice £2
Layla Wednesday Crisps £3
Emma Friday Cookie £4
Solving these mysteries teaches you to convert real-world statements into algebraic conditions and deduce unseen values – excellent training for word-problem mastery and logical deduction.

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