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Alkatran
Oct27-04, 09:48 AM
7. At Uptown University, language courses are o ered in French and Span-
ish. 47% of the students study French and 39% study Spanish. 22% of
the students study both French and Spanish.
(a) What percentage of the students study a language (French or
Spanish)?
(b) What is the probability that a student studies French but not
Spanish?
(c) A student is selected randomly. Are the events A=fthe student
studies Frenchg and B=fthe student studies Spanishg indepen-
dent? Why or why not?

my answers:
(a) F or S = F + S - F and S = .47 + .39 - .22 = 64%
(b) F and (not S) = F - F and S = .47 - .22 = 25%
(c) No, F*S <> 22%

I got (b) wrong. On the answer sheet (this is a practice midterm) there is:
.47-.22.25 (draw a picture of the events to see this)

Well I drew a picture and I still think it's .47 - .22, not .47 - .22*.25

:grumpy:

uart
Oct27-04, 11:17 AM
I got (b) wrong. On the answer sheet (this is a practice midterm) there is:
.47-.22.25 (draw a picture of the events to see this)

Hmmm, have you considered that the given answer may be a typo that is supposed to read, 47-.22 = .25 (draw a picture of the events to see this)

Alkatran
Oct27-04, 11:36 AM
Hmmm, have you considered that the given answer may be a typo that is supposed to read, 47-.22 = .25 (draw a picture of the events to see this)

Yes, that's why I posted here to confirm.

uart
Oct27-04, 12:08 PM
Ok then, let me confirm that I'm pretty sure that 0.25 is the correct answer. :)

Alkatran
Oct27-04, 02:10 PM
Ok then, let me confirm that I'm pretty sure that 0.25 is the correct answer. :)

That is Excellent