Answer:
There is a 0.15625 = 15.625% probability that you choose each answer at random and get 4 of the questions correct.
The formula for the probability of x successes is:
The parameters are given by:
n is the number of trials of the experiment.
p is the probability of success on a single trial of the experiment.
For this problem, we have that:
There are 5 questions, hence n = 5.
Each question has two options, true or false, p = 1/2.
The probability of 4 correct is given by P(X = 4)
P(X = 4) = 5 x (0.5)^4 x (0.5) = 0.15625.
0.15625 = 15.625% probability that you choose each answer at random and get 4 of the questions correct.
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