Question

Complete the two-way frequency table below, which shows the relationship between student gender in a particular class and whether students wear jeans. From a sample of 30 students, it is found that there are 18 females, 20 people in the class who are wearing jeans, and 5 females not wearing jeans.
What is the probability (rounded to the nearest whole percent) that a student will be a female given that he or she wears jeans? Are the events being female and wearing jeans independent?

Answer 1

@wilsondanielle how would i solve this?

Answer 2

start by breaking everything down into probability (make fractions, reduce to decimal)

Answer 3

i dont get sorry

Answer 4

eg : the probability someone in the class is female is 18/30 or 0.6.
The probability someone is wearing jeans is 20/30 or 0.667

Continue on in that fashion!

Answer 5

ok

Answer 6

they are independent right and do i times the two together?

Answer 7

A. 43%; they are not independent
B.65%; they are not independent
C. 72%; they are independent
D.65%; they are independent

Answer 8

would it be D

Answer 9

probability of being female : 0.6
probability of wearing jeans : 0.667

probability of being female and NOT wearing jeans : 5/18 = 0.277
probability of being female and wearing jeans : 13/18 = 0.722
Both calculated from data in the question

Therefore :
If the student is wearing jeans, there is a 13/20 chance they are female - or 0.65%. Does this seem like a dependent or an independent event?

Answer 10

dependent

Answer 11

so the answer would be B? @wilsondanielle

Answer 12

is p(female)xp(jeans) = p(female + jeans)?