Question

In a group of 92 students 40 have brown eyes, 35 have hazel eyes, and 17 have blue eyes. Find the probability that a student picked from this group at random either has hazel or brown eyes? Enter your answer as a fraction in the form a/b (for example 2/3, 5/7) or as an integer.

Answer 1

as a fraction = 75/92

as a percentage = 81.52%

Explanation:

total no of students = 92

probability that a student has hazel or brown eyes = Pr(hazel or brown)

but probability of a or b happening ie Pr(a or b) simply is Pr (a) +Pr (b)

therefore Pr(hazel or brown) = Pr(hazel)+ Pr(brown)

Pr(brown) = (no of brown eyes )/(total set of eyes)

=
`40/92` = 10/23

Pr( hazel) = (no of hazel eyes )/(total set of eyes)

=
`35/92` =35/92

hence Pr(hazel or brown) = (10/23) + (35/92) =75/92

so there's 75/92 probability (or 0.8 out of 1 chance )to choose either hazel or brown randomly