🚀 Space Math Explorers

TEACHER-GUIDE-VERIFIED · TG-V9-052

1. Star brightness drops from 10,000 to 9,900 units. Find the percent decrease.

Verified solution

Solution: Decrease=100. Percent=100/10,000 x 100%=1%.

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-V9-052

Measure a Star Brightness Drop (TG-V9-052)

Brightness falls from 10,000 to 9,900 units: a decrease of 100 units, or 1% of the original brightness. Check that 99% remains; this calculation does not establish the physical cause of the drop.

Space Math Explorers · approved worked example · 0:59 · 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.