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Variable Vault Level 1 Hard maths puzzle involving algebra, clues, codeword and dials

Variable Vault – Level 1 – Hard

Home » Puzzles » Variable Vault » Level 1 - Hard » Variable Vault – Level 1 – Hard
Topics: algebra, clues, codeword, dials, linear equations, systems of equations

Four lettered dials (A, B, C, D) unlock a vault. Each dial must be set to the correct number based on the clues below. Solve all clues to find the code: the 4-digit number ABCD.

Crack the vault code using these clues:

– A = 2(C – 1)
C + B + D + A = 21
C – 2 = D – 2
B + D = A
A is an even number greater than 4.
C = (B + D + 2) ÷ 2

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Additional instructions for Variable Vault (Level 1, Hard)

Variable Vault – Hard

Sign errors are the main danger. Hard puzzles often include negatives, subtraction across brackets, or multiple variable terms.

  • Expand brackets slowly.
  • Check every sign when collecting terms.
  • Substitute back to confirm solutions.

If a result looks strange: re-check the last bracket expansion.

Full help: Variable Vault

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