in a group of 200 students, 138 are enrolled in a history class, 115 are enrolled in a math class, and 91 are enrolled in both. What is the probability that a randomly selected student is enrolled in a history class but not a math class?
A. 69/100
B. 47/200
C. 91/200
D. 18/25

Question

in a group of 200 students, 138 are enrolled in a history class, 115 are enrolled in a math class, and 91 are enrolled in both. What is the probability that a randomly selected student is enrolled in a history class but not a math class?
A. 69/100
B. 47/200
C. 91/200
D. 18/25

mathstudent55 · Answer

Are you familiar with Venn diagrams?

mathstudent55 · Answer

A Venn diagram is a way of showing graphically sets and how they intersect.

mathstudent55 · Answer

There are 200 students:

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anonymous · Answer

yes

mathstudent55 · Answer

Of the 200 hundred students, some have only history; others have only math; others have both. We use intersecting circles to represent the sets of students taking history and math.

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mathstudent55 · Answer

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