Take a guess: A student takes a multiple-choice test that has 7 questions. Each question has five choices. The student guesses randomly at each answer. Let X be the number of questions answered correctly. Round the answers to at least four decimal places. Find the probability that x is equal to 4:

Answer:
Given:

Probability of success $(p) = 1/5 = 0.20 $

Sample size $(n) = 7 $

Solution:
The probability that x is equal to 4:
$P(x = 4) = \binom{7}{4} \cdot 0.2^4 \cdot (1 – 0.2)^{7-4} = 0.0287$

Final Answer:
The probability that x is equal to 4 = 0.0287

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