Solved IB ACIO Question
A solved IB ACIO PYQ - decoded step-by-step.
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Q · Missing Numbermedium · 45s
Identify the missing number:1, 3, 6, 10, 15, ?
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.
Triangle numbers sequence; next number is 20.
Final Answer: Option A - 20