What is the next number in the alternating operation sequence: 3, 6, 5, 10, 9, 18, 17, ___?
Answer and explanation
Correct answer: A. 34
- Step 1: Identify the pattern of operations: 3 2 = 6; 6 - 1 = 5; 5 2 = 10; 10 - 1 = 9; 9 2 = 18; 18 - 1 = 17. Step 2. The next operation is multiply by 2: 17 2 = 34. Answer: 34, multiplying 17 by 2 following the alternating rule of multiplying by 2 and subtracting 1. Why not the others: 33 subtracts 1 when multiplication was due.
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