Solved IB ACIO Question
A solved IB ACIO PYQ — decoded step-by-step.
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Q · Missing Numbermedium · 45s
Find the missing number: 81, 64, 49, 36, 25, ?
TopicMissing Number
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.
Decreasing squares: 9², 8², 7², 6², 5², next 4²=16.
Final Answer: Option C — 16