Question

Juanita has a bag of marbles. Without looking, she removes one marble, notes the color and replaces it. She repeats this process 70 times and records the results in the table below. What is the probability that she will pick a blue marble on her 71 st try

Answer 1

Given table:

color ----- Frequency

Red ------ 14

Green ----- 19

Blue -------- 21

Yellow ----- 16

Number of process repeated (trials) = 70 times

Probability (event) = number of times the event occurs / total number of trials

From the table we can see that the number of times she pick the blue marble is 21

Probability of picking a blue marble on next try = $\frac{21}{70}$ = $\frac{3}{10}$