Sets 3
2 marks · NormalIn a survey of 60 students, 38 play football (F), and 15 play both football and tennis (T). A student is chosen at random. Calculate the probability that the student plays tennis given that they play football.
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15/38
Also accept: 0.395; 0.395...
Common mistakes: Dividing by the total number of students (60) instead of by the number who play football (38)
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Marking points
M1 · 1 mark · Identifies that the denominator should be the number of football players (38), not the total number.
A1 · 1 mark · Correct final answer: or equivalent decimal.
Worked solution
Given: Number of football players (F) = 38, number who play both football and tennis = 15.
Probability a student plays tennis given they play football is: