A topic you 'somewhat know' is a topic you don't know yet. Be honest about your weak areas.

SOF IMO · Free quiz

SOF IMO — free 5-question quiz

No signup needed. Answer 5 questions in the SOF IMO pattern, get instant scoring and solutions, then unlock full mocks and your weak-topic map for free.

Question 1 of 5

Medium

Complete the following 3×3 matrix by finding the pattern. What number should replace the question mark? Row 1: 7, 10, 13 Row 2: 11, 14, 17 Row 3: 15, 18, ?