Practice Experimental Probability in Statistics
Use these practice problems to test your method after reviewing the concept explanation and worked examples.
Quick Recap
The probability of an event based on actual experimental data: the number of times the event occurred divided by total trials.
You flip a coin 100 times and get 53 heads. Your experimental probability is \frac{53}{100} = 0.53. It's based on what DID happen, not what should happen theoretically.
Example 1
easyA student flips a coin 50 times and gets 28 heads and 22 tails. What is the experimental probability of getting heads?
Example 2
mediumA bag contains an unknown number of red and blue marbles. In 80 draws (with replacement), 52 red and 28 blue marbles were drawn. (a) Estimate the probability of drawing a red marble. (b) If there are 20 marbles total, estimate how many are red.
Example 3
mediumA spinner has sections coloured red, blue, and green. After 120 spins, the results are: Red 45, Blue 50, Green 25. (a) Find the experimental probability of each colour. (b) Do you think the spinner is fair (equal sections)? Justify your answer.
Example 4
hardA basketball player made 72 out of 100 free throws in practice. (a) What is her experimental free-throw probability? (b) In the next game, she attempts 15 free throws. How many would you expect her to make? (c) Why might the actual number differ from your prediction?