csat-suneung 2025 Q26

csat-suneung · South-Korea · csat__math 3 marks Combinations & Selection Combinatorial Probability
A survey was conducted on the preferences for Subject A and Subject B among 16 students in a class. Each student who participated in the survey chose one of the two subjects. 9 students chose Subject A and 7 students chose Subject B. When 3 students are randomly selected from the 16 students who participated in the survey, what is the probability that at least one of the 3 selected students chose Subject B? [3 points]
(1) $\frac{3}{4}$
(2) $\frac{4}{5}$
(3) $\frac{17}{20}$
(4) $\frac{9}{10}$
(5) $\frac{19}{20}$
A survey was conducted on the preferences for Subject A and Subject B among 16 students in a class. Each student who participated in the survey chose one of the two subjects. 9 students chose Subject A and 7 students chose Subject B. When 3 students are randomly selected from the 16 students who participated in the survey, what is the probability that at least one of the 3 selected students chose Subject B? [3 points]\\
(1) $\frac{3}{4}$\\
(2) $\frac{4}{5}$\\
(3) $\frac{17}{20}$\\
(4) $\frac{9}{10}$\\
(5) $\frac{19}{20}$