. Two balls are randomly selected with replacement from a jar that contains seven red and three white balls. The number x of red balls is recorded.

Question

If the experiment is binomial, give the values of n and p. (If the experiment is not binomial enter NONE.)

n=2

Answer 1

Hi Halle.

This is a binomial experiment because of four things:

(1) The number of trials is fixed (only two balls are selected)

(2) Each trial is independent of each other (because the balls are replaced after being drawn, the probability of drawing a red will stay the same for each trial)

(3) The probability of success stayed the same for each trial

(4) Each trial either gives a success (red ball drawn) or a failure (not a red ball drawn).

To find p and n, we need to know what they represent.

p: the probability of a success (drawing a red ball)

n: the number of trials

The probability of drawing a red ball is 7/10 = 0.7 because there are 7 red balls and 10 balls in total (add the red and white balls to get the total). So p = 0.7.

The number of trials is 2 because two balls are drawn. So n = 2.

Please let me know if you have any questions.