IMAT 2012 Q 77 Math: Probability

In a group of students, exactly 2/5 are male and exactly 1/3 study mathematics. The probability that a male student chosen at random from the group studies mathematics is p.
Which of the following is the range of possible values of p?
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Hi, I know if none of the males study maths then 0 could be its lowest value. However, how do you find the highest value?