Work through the levels in order. Type your answer and press Check — open the worked solution if you get stuck. Answers like -6, 3/4 or 0.25 are typed exactly as shown. A ⭐ Bonus Challenge at the end is extra credit — skip it if the rest was hard work.
Level 1 · Warm-up
1 Pattern 4, 7, 10, 13: what comes next?
Show worked solution
+3 → 16.
2 Sticks = 3 × step + 1. How many sticks at step 5?
Show worked solution
3×5+1 = 16.
3 Perimeter of ONE unit square?
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4 sides of 1 → 4.
Level 2 · Core
4 Table: 1→5, 2→9, 3→13. Across rule? (as a rule)
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Grows 4; 1×4=4, +1 → ×4+1.
5 Same pattern: count at step 25?
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4×25+1 = 101.
6 A 3×3 garden gets a 1-tile border. How many border tiles?
Show worked solution
5×5 − 3×3 = 25 − 9 = 16.
Level 3 · Challenge
7 Squares joined in a row have P = 2n + 2. How many squares if the perimeter is 30?
Show worked solution
Backwards: 30 − 2 = 28, ÷ 2 = 14 squares.
8 Triangles in a row: sticks 3, 5, 7, … Is 24 ever the stick count?
Show worked solution
Counts are always ODD (2n+1) → no.
9 A 10×4 pool with a 1-tile border: how many border tiles?
Show worked solution
12×6 − 10×4 = 72 − 40 = 32.