Amanda, this is the solution:
Step 1: Let's calculate the percentage of students that chose science fiction as their favorite movie genre.
• Science fiction percentage = 100 - 40 - 30 - 10
,
• Science fiction percentage = 100 - 80
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• Science fiction percentage = 20
Step 2: Now, let's find the number of students that represent the 20% that chose science fiction.
• Number of students that chose science fiction = 20% * 40
,
• Number of students that chose science fiction = 0.2 * 40
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• Number of students that chose science fiction = 8