Download Coin experiments

Coin Experiments
It is well known that the chance of getting a head when we toss a coin is ½.
But let’s try two variations on the traditional coin experiment.
Coin Experiment #1
Directions:
- Stand a penny on edge on a hard, flat surface.
- Hit the surface with your hand so that the penny falls over.
- Do this at least 30 times.
- On the table below, record (tally) what side is facing up (heads or tails) each time
the penny falls.
- Then add your group’s data to your tally (in a different color).
Heads
Tails
Questions:
1- What percentage of the time did heads land upward?
2- Do you think this is a good estimator of the actual probability of heads landing
upward? Why or why not? Any confounding variables?
3- The probability you found should not be the same as the probability of getting
heads upwards when you toss a coin in the air. Why do you think they are
different?
4- Which outcome is more likely in this type of coin flip? Why do you think this is
so?
Coin Experiment #2
Directions:
- Hold a penny upright on its edge under your pointer-finger on a hard, flat surface.
- With your other pointer-finger, flick the penny so that it spins for some time
before falling
- Do this at least 30 times.
- On the table below, record (tally) what side is facing up (heads or tails) each time
the penny falls.
- Then add your group’s data to your tally (in a different color).
Heads
Tails
Questions:
1- What percentage of the time did heads land upward?
2- Do you think this is a good estimator of the actual probability of heads landing
upward? Why or why not? Any confounding variables?
3- The probability you found should not be the same as the probability of getting
heads upwards when you hit the table (experiment #1) or when you toss a coin in
the air. How were these probabilities different? Why do you think they were
different? How were the two experiments different?
4- Which outcome is more likely in this type of coin flip? Why do you think this is
so?