Question

3. A multiple choice test contains 15 questions. Each question has four options, only one of
which is correct. What is the probability of guessing exactly 9 questions correctly?

Answer 1

Answer:

$\frac{5005\times 3^6}{4^{15}}$

Step-by-step explanation:

by using binomial property, we get the probability

$P=C^{15}_{9}\times \frac{1}{4^9}\times \frac{3^6}{4^6}$