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Giving a test to a group of students, the grades and gender are summarized below A B C Total Male 2 19 7 28 Female 4 9 14 27 Total 6 28 21 55 If one student is chosen at random, Find the probability that the student was female OR got a(n) "B". (Please enter a reduced fraction.)

User Gralex
by
6.8k points

1 Answer

6 votes

Answer:

46/55

Explanation:

A B C Total

Male. 2 19 7 28

Female. 4 9 14 27

Total. 6 28 21 55

Total number of students = 55

Pr of picking a female = number of females / total number

= 27/55

There are 27 females and 28 people got a B

Number of females or those who got a B = 27 + 28 = 55

Subtract off 9 females who got B to help correct for double counting . We have 55 - 9 = 46

This means there are 46 people who either got a B, are females or are females who got a B

Pr(female or got a B) = number who are females or got a B / total number

= 46/55

User Christianleroy
by
6.7k points
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