Q: A completely unprepared student is given a true/false type of test which contains 10 questions. What is the probability that the student will, by selecting the answers at random, get all answers right?
It is later decided that a pass will be awarded or 8 correct answers. What is the probability of the student passing the test?
Answer:
For first part, using X~Bin (10, 0.5)
P(X=10) = 10C0 x 0.5^10 = 0.0009766
For the second part,
P(X ≥ 8) = 1 - P(X ≤ 7) = 1 - 0.9453 = 0.0547
Conclusion: There is only a 0.09766% chance of getting full marks and a 5.47% chance of passing.
Moral of the story: Even if it kills you Esther, please study Physics before the test date. =.=
And the same goes for the rest. Guessing game never helps. GOOD LUCK FOR TOMORROW!
Subscribe to:
Post Comments (Atom)
0 comments:
Post a Comment