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n an after school program, students must choose to either play on the playground or read a book silently. On one cloudy day, 70% of the students chose to play on the playground, and the rest chose read a book silently. 60% of the students who went to the playground are boys, and 20% who stayed inside to read a book are boys. If a student is randomly selected on this day, what is the probability that the student is a girl?

User SHiRKiT
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1 Answer

3 votes
20% b/c
70% playground - 60% boys= 10%girls
100% total-70% playground = 30% inside
30% inside-20% boys= 10%girls
10%girls +10% girls=20%girls
User Shadowtrot
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