Agroup of 8 friends (5 girls and 3 boys) plans to watch a movie, but they have only 5 tickets. if they randomly decide who will watch the movie, what is the probability that there are at least 3 girls in the group that watch the movie?

The total number of ways 5 people can be selected out of 8 is 8C5 (combination of 8 taken 5) which is equal to 56. Given the conditions that at least three girls should watch the movie.
(1) girls - 3  ; boys - 2      ;    (5C3) x (3C2) = 30
(2) girls - 4  ; boy - 1        ;    (5C4) x (3C1) = 15
(3) girls - 5  ; boy - 0        ;    (5C5) x (3C0) = 1

Adding all the three possibilities, 46. The probability is the ratio of this value and the total number, 56. Thus, the answer is approximately 0.80.