Probability question. (must be in decimal form)

Question

Question. The probability that Samantha gets a multiple-choice question correct is 0.6. Sammantha attempts 3 multiple choice questions. The probability that she gets at least one correct is:

Answer 1

The easiest way to calculate problems of the form at least one is to calculate 1 - P(0)

P(0) means all 3 are not correct.

P(incorrect) = 1 - .6 = .4

Thus, P(0) = P(all 3 incorrect) = .4 ^ 3 = .064, and

1 - P(0) = 1 - .064 = .936