Chrome File Edit View History tookmarks Window Help Kenexa x

Chrome File Edit View History tookmarks Window Help Kenexa x LON-CAPA x Secure https://s4 lite msu. Mary Lilly Rossi v (Student section: 742) MTH1 12, ng 2017-Finite Mathematics: Applications of College Algebra Sprit Messa f Help Logou course contents Lecture sb Problems Tuberculosis Tests Trmer Notes evalu Feedback Print Tuberculosis Tests The students of a university are examined for tuberculosis by a chest x-ray. A negative x-ray indicates the student does not have present. Suppose that a has a chance of having it detected by the X-ray, while a student has a chance indicates the student has the disease). Statistics predict that 0.2% of the students will actually have tuberculosis. a. What is the probability of a student\'s not having TB? o.99so the disease, a positive X-ray indicates the disease is of having a false positive (the X-ray wrongly ou are correct, \'Your receipt no. is 147-6154 Previous Tries b. what is the probability of a student\'s x-ray being positive? oeese raw a tree diagram. and fill in the necessary numbers. incorrect. Tries 3/8 erevious thes c. Suppose a certain student\'s x-ray is positive. What is the probability that the student actually has the disease? Sutmit Answer Tries 0/8 Post Discussion Send Feedback MacBook Pro

Solution

Solution:-
qa) 100 - 0.2 = 99.8 %

qb) 0.95*0.002 + 0.07*0.998 = 0.0019 + 0.06986 = 0.07176 or 7.176%

qc) P[diseased | +ve X-ray] 0.95*0.002/0.07176 = 0.0019/0.07176 = 0.026477 = 2.65%

Answer:- (a) 99.8 % (b) 7.176% (c) 2.65%