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Question How would you change this game to make the final answer 3? What about 5?
(a) We can understand such tricks through algebra. Step 1: Think of a number = x Step 2: Triple it = 3x Step 3: Add 9 = 3x + 9 Step 4: Divide by 3 = \(\frac{3 x+9}{3}\) = x + 3 Step 5: Subtract the original number you thought of (x + 3) – x = 3. For Example: Consider a number 23. Triple it = 3 × 23 = 69 Add 9 = 69 + 9 = 78 Divide by 3 = 78 ÷ 3 = 26 ∴ 26 – 23 = 3 (b) To make the final answer 5. Step 1: Think of a number = x Step 2: Double it = 2x Step 3: Add 10; 2x + 10 Step 4: Divide by 2 = \(\frac{2 x+10}{2}\) = x + 5 Step 5: Subtract the original number = x + 5 – x = 5