Solved IB ACIO Question
A solved IB ACIO PYQ — decoded step-by-step.
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Q · Series (Numeric and Alphanumeric)medium · 45s
What is the next term in the series: 1, 3, 7, 15, 31, ...?
TopicSeries (Numeric and Alphanumeric)
Question Typemultiple choice
Difficultymedium
Marking+1 / −0.25
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
Each term doubles the previous term plus 1: 1×2+1=3, 3×2+1=7, 7×2+1=15, 15×2+1=31. Next term: 31×2+1=63.
Final Answer: Option A — 63