Mrs. Jones surveys her class of 20 students about their siblings. In the class, 15 have a brother, 16 have a sister, and 12 have both a brother and a sister. What is the probability that a student has a brother OR a sister?

Question

Cody Hinton

Mathematics

13 March, 09:36

Mrs. Jones surveys her class of 20 students about their siblings. In the class, 15 have a brother, 16 have a sister, and 12 have both a brother and a sister. What is the probability that a student has a brother OR a sister?

+1

Answers (2)

Know the Answer?

Hugo Quinn · Answer 1

P (Brother or Sister) =.75 +.82 -.65 P (Brother or Sister) =.92 = 92% The reason you subtract the. 65 is that scenario does not fit the rule. The rule is the probability of having a brother OR a sister. The. 65 represents the kids who have both not either.

Damon Lane · Answer 2

About 10 % of people might have a brother or sister