TEACHER-GUIDE-VERIFIED · TG-V9-057

6. Of 60 solar events, 38 are flares, 27 are plasma eruptions, and 15 are both. How many are in at least one group?

Verified solution

Solution: Use inclusion-exclusion: 38+27-15=50 events.

Source: Teacher Guide V9 · English V9. Match the numbers and wording in your printed question before using this solution.

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VIDEO HELP · TG-V9-057

Count Events in At Least One Group (TG-V9-057)

Count each solar event once: add 38 flares and 27 plasma eruptions, then subtract the 15 overlapping events to get 50. Check all four Venn regions.

Space Math Explorers · approved worked example · 1:37 · Watch on YouTube

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These pages reproduce verified solution steps for the registered V9 questions. It does not diagnose learning needs or replace instruction from a qualified teacher or tutor.