Question

Carey has a bag of marbles. There are 4 red marbles, 5 blue marbles, and 1 green marble. She conducted an experiment in which she pulled out one marble and recorded the color and then returned it to the bag 50 times. Her results are shown in the table.

Result Tally Total
Red
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∣
∣
∣
∣
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22
Blue
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∣
∣
∣
∣
∣
∣
∣
∣
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24
Green
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4
What is the difference between the theoretical probability and the experimental probability of picking a green marble?

Answer 1

0.02 or 2%

Explanation:

Theoretical probability calculated by dividing the number of events you want to calculate(green marble) with the total event possible(red + blue + green). There are 4 red marbles, 5 blue marbles, and 1 green marble. The probability will be: 1/(4+5+1)= 1/10= 10%

The result of the experiment is:

Red=22

Blue= 24

Green=4

Experimental probability calculated by dividing the number of events occurs with the total number of trials. We pull green 4 times and do 50x pulls, so the probability is: 4/50= 8%

Difference between the theoretical probability and the experimental probability is: 10%- 8%= 2%