Question

Based on the data in this two-way table, if a girl is randomly selected, what is the probability that she will have above-average grades?

Gender/Grade Below Average Above Average Total
Boy 14 23 37
Girl 16 22 38
Total 30 45 75
A.
0.29
B.
0.51
C.
0.58
D.
0.60

Answer 1

previous solution was removed for plagiarism

that being said, this is a conditional probability. " if a girl is randomly selected, what is the probability that she will have above-average grades?" it is given that a girl is selected, so the denominator should be the total number of girls

out of that set, we want the girls who have above-average grades

so check the two-way table, find (number of girls who have above average grades) and divide by the total # of girls