SIMCC game documentation

Maths Mastermind — Rulebook

Maths Mastermind is a solo arithmetic challenge. Each card gives you four numbers and one target. Build an expression that equals the target exactly.

1. The card

A card contains:

• four number slots;
• one target from 0 to 99 on Easy and Medium, or 1 to 99 on Hard; and
• a difficulty: Easy, Medium or Hard.

Repeated values occupy separate slots. Two slots that both show 1/3 are two usable numbers, not one number printed twice by mistake.

2. Building an expression

Use at least two of the four number slots. A slot may be used at most once in one answer. You do not have to use all four slots.

The available operations are addition (+), subtraction (−), multiplication (×) and division (÷). Parentheses may be used to control the order of evaluation.

Standard order of operations applies: multiplication and division before addition and subtraction, unless parentheses say otherwise. Division by zero is not allowed.

3. Exact arithmetic

Answers use exact rational arithmetic. Fractions are not converted to rounded decimals, so 1/3 + 1/3 is exactly 2/3.

Your final value must equal the target exactly. A complete wrong answer stays open so you can undo, clear or revise it and try again.

4. Difficulty

• Easy: whole-number cards and whole-number targets.
• Medium: may include one fraction; targets are usually whole numbers.
• Hard: includes one or two fractions and excludes a zero target.

Every generated card carries a verified solution. Other valid solutions may exist and are accepted.

5. Controls

Select card numbers with the on-screen controls or keys 1–4. Operator keys, parentheses, Backspace, Escape and Enter work directly. H shows a first-step hint and N loads a new card.

Revealing the stored solution does not assert that it is the only possible solution.

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