9.1 Two events A and B are such that:
- P(not A) = 0,45
- P(B) = 0,3
- P(A or B) = 0,685
Are events A and B independent? Justify your answer
9.2 A survey was done among a group of 75 learners to determine which sports they
watch on television. They chose from athletics (A), netball (N) and rugby (R). Some
of the information that was collected is as follows:
- 12 learners watch netball, rugby and athletics
- 25 learners watch rugby and athletics
- 22 learners watch netball and athletics
- 38 learners watch rugby
- 5 learners watch only netball and rugby
- 9 learners watch netball only
- 4 learners watch athletics only
The Venn diagram below shows the information:
9.2.1 Determine the values of a, b, c and d. (4)
9.2.2 Calculate the probability that a learner selected at random watches athletics or
both netball and rugby. (3)
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