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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:

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

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Additional instructions for Variable Vault (Level 1, Hard)

Variable Vault – Hard

Hard puzzles combine multi-step algebra and precision. Expect to factorise, expand, rearrange, and extract specific components accurately.

Hard-mode plan:

  • Preview all clues before starting.
  • Identify heavy algebra steps (factorising, multi-bracket expansion).
  • Keep each answer clearly labelled and boxed.

Vault rule: only move forward once the current result is verified.

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