A bag holds 2 yellow, 1 green, and 2 red marbles. If you were to draw a marble from the bag 150 times, and replace it after each draw, how many yellow marbles would you expect to draw? (1 point)
A:50
B:60
C:30
D:38
I say it's B or A
Nvm i worked it out it's B
Hmmm. I agree with that answer is best, but to get 60 marbles in 150 draws would very seldom happen. In fact, it happens with a frequency of only .0664. Getting exactly 59 or 61 is almost the same...0.0653 and .0569 frequency.
http://ncalculators.com/statistics/binomial-distribution-calculator.htm
Your probablity of success (getting yellow) is .4 in the above question.
If your rich bud wanted to bet you a wager on getting exactly 60 yellow out of 150 tries, take him on, and make $$.
To calculate the expected number of yellow marbles you would draw, you need to find the probability of drawing a yellow marble and then multiply it by the total number of draws. In this case, there are 2 yellow marbles out of a total of 2 yellow + 1 green + 2 red = 5 marbles.
The probability of drawing a yellow marble on any particular draw is:
Probability of drawing yellow marble = Number of yellow marbles / Total number of marbles
Probability of drawing yellow marble = 2 / 5
Now, to find the expected number of yellow marbles, you multiply the probability by the total number of draws:
Expected number of yellow marbles = Probability of drawing yellow marble * Total number of draws
Expected number of yellow marbles = (2 / 5) * 150
Calculating the above equation gives us:
Expected number of yellow marbles ≈ 60
So the correct answer is B: 60 yellow marbles.