Data Set 7-1: Suppose an urn (a kind of jar that seems to be the best natural habitat for marbles) contained 3 red, 6 black, 5 blue, 2 yellow and 4 green marbles.
-Refer to Data Set 7-1. The probability of drawing a black or a green marble is
A) .06
B) .40
C) .60
D) none of the other alternatives are correct

Question

Quizplus · Accepted Answer

The total number of marbles is 3 + 6 + 5 + 2 + 4 = 20. The probability of drawing a black or green marble is the sum of the probabilities of drawing a black marble and drawing a green marble, which is (6/20) + (4/20) = 10/20 = 0.5. None of the provided alternatives match this calculation.

Data Set 7-1: Suppose an Urn (A Kind of Jar