Question

Using a 16-sided number cube, what is the probability that you will roll a multiple of 4 or an odd prime number? The number 1 isn't an odd prime. Round to three decimals.
A. 0.625
B. 0.250
C. 0.563
D. 0.688

Answer 1

Answer: 0.563 (choice C)

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Explanation:

E = event space

E = set of outcomes we want to happen

E = rolling a multiple of 4 or rolling an odd prime number

E = {4,8,12,16     3,5,7,11,13}

n(E) = number of items in set E

n(E) = 9, (four multiples of 16+five ways to roll odd prime number)

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S = sample space

S = set of all possible outcomes (whether we want them to happen or not)

S = {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16}

n(S) = number of items in set S

n(S) = 16

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P(E) = probability of event space occurring

P(E) = probability of rolling a multiple of 4 or rolling an odd prime number

P(E) = n(E)/n(S)

P(E) = 9/16

P(E) = 0.5625

P(E) = 0.563