SOLUTION: on a 10 question multiple choice test, each question has 1 correct response and three that are incorrect. If at random, a student circles an answer for each question: a) What is t

Algebra ->  Probability-and-statistics -> SOLUTION: on a 10 question multiple choice test, each question has 1 correct response and three that are incorrect. If at random, a student circles an answer for each question: a) What is t      Log On


   

Question 275790: on a 10 question multiple choice test, each question has 1 correct response and three that are incorrect. If at random, a student circles an answer for each question:
a) What is the probability that she will get the first three and last two right?
1/4 x 1/4 x 1/4 x 3/4 x 3/4 x 3/4 x 3/4 x 3/4 x 1/4 x 1/4
= 2.317428589x10%5E-04
b) What is the probabilty that she will get any 5 right?
+P%28A%29=n%28A%29%2Fn%28S%29+
Let: n%28A%29=+10C5
Let: n(S)= 5%5E%281%2F4%29 and 5%5E%283%2F4%29
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
on a 10 question multiple choice test, each question has 1 correct response and three that are incorrect. If at random, a student circles an answer for each question:
a) What is the probability that she will get the first three and last two right?
1/4 x 1/4 x 1/4 x 3/4 x 3/4 x 3/4 x 3/4 x 3/4 x 1/4 x 1/4
= 2.317428589x10%5E-04
b) What is the probabilty that she will get any 5 right?
P(x=5) = 10C5*(1/4)^5*(3/4)^5
= binompdf(10,1/4,5) = 0.0584..
Cheers,
Stan H.