Answer to Question #147156 in Statistics and Probability for Vladimyr Lubin

Question

(5.2.19) Assume that random guesses are made for 8 ​multiple-choice questions on a test with 5 choices for each​ question, so that there are n=8 ​trials, each with probability of success​ (correct) given by p=20. Find the probability of no correct answers.
The probability of no correct answers is?

Answer 1

Solution:

The probability of success: $p=0.2$

$P(X=0)=_0C_8 \times p^0 \times q^8=1\times1\times0.8^8=0.1678$

Answer: Probability of no correct answers is 0.1678