Question

You have a jar of marbles in front of you with the following colors: 12 are red, 17 are blue, 8 are yellow, and 13 are white. Suppose you had a larger jar of 250 marbles with the same ratio of colors. What is the probability of selecting either a red or white marble from the larger jar?

Answer 1

Answer: 12+17+8+13=50, meaning that if we wanted to scale the amount of marbles to 250, we would need to multiply by 5.

So, if we multiply each amount of marbles times 5, that would give us:

60 red marbles

85 blue marbles

40 yellow marbles

65 white marbles

now, the probability of selecting a red or white marble from the jar of 250 marbles, you would need to add together the amount of white and red marbles, and divide that by 250.

60 + 65= 125 / 250

Wwe could stop there if the question wants the answer in fractions, and just simplify, but if it needs the answer in a percentage, then you would still divide 125 by 250.

125/250=0.5

0.5 is equal to 50%

(If the fraction needs to be simplified it would be 5/10, which is also 1/2.)