Answer:
The probability that she is correct on only two questions is 0.246
Explanation:
The probability of getting an answer correct = 1/5
The probability of getting only two questions correctly
By binomial trials, we have;
P(X = K) = [tex]\dbinom{n}{k}\times p^{k}\times \left (1 - p \right )^{n - k}[/tex]
P(X = 2) = [tex]\dbinom{6}{2}\times \left (\dfrac{1}{5} \right )^{2}\times \left (1 - \dfrac{1}{5} \right )^{6 - 2}[/tex]
= 15×256/15625 = 768/3125 = 0.246
Therefore, the probability that she is correct on only two questions = 0.246.