Answer: 3/4, because the probability of renting a comedy is 1/4
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Explanation:
We have 36+26+30+28 = 120 students. 30 of which rented a comedy.
The probability of renting a comedy is 30/120 = (30*1)/(30*4) = 1/4
The probability of not renting a comedy is 1 - (1/4) = 4/4 - 1/4 = (4-1)/4 = 3/4.
Or you could say that 1/4 = 0.25, so 1-0.25 = 0.75 which converts to the fraction 3/4.
If you had 4 people and 1 of them rents a comedy, then the other 3 hasn't rented a comedy.