A multiple-choice quiz has 15 questions, each with 4 possible answers of which only 1 is the correct answer. What is the probability that a student gets at least 1 correct answer?
0.0188
To find the probability that a student gets at least 1 correct answer in a multiple-choice quiz, we can consider the complementary probability. The complementary probability is the probability of the opposite event occurring, which in this case is the probability of a student getting no correct answers.
Let's calculate the probability of getting no correct answers first.
For each question, there are 4 possible answers, and only 1 of them is correct. So, the probability of getting a specific question wrong is 3/4, and since there are 15 questions, the probability of getting all the questions wrong is (3/4)^15.
Next, we can find the probability of getting at least one correct answer by subtracting the probability of getting no correct answers from 1:
Probability of getting at least one correct answer = 1 - Probability of getting no correct answers
Therefore,
Probability of getting at least one correct answer = 1 - (3/4)^15
Now, let's calculate this probability.