Solved IB ACIO Question
A solved IB ACIO PYQ — decoded step-by-step.
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Q · Series (Numeric and Alphanumeric)medium · 45s
Identify the next term: 11, 21, 43, 87, ...?
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 number plus 1: 11×2+1=23, but the series jumps differently. Actually, the difference doubles: 10,22,44. Next difference 88. So 87+88=175.
Final Answer: Option D — 176