This experiment is designed to help students see that the probability is not the same as reality. However, they should discover that as we do the experiment more times, the results resemble the probability more closely.
For each student:
Most of us would guess that the probability of flipping heads on a coin are one out of two, or 1/2. The students can readily understand this. However in practice, the result of flipping a coin ten times will not always come up 5 heads and 5 tails. This experiment is designed to help students see that the probability is not the same as reality. As we do the experiment more times, however, the results resemble the probability more closely.
Benford’s law shows that there is a high probability that either heads or tails will come up six or more times in a row when the coin is tossed 200 times. Most fakers will not know this and will not put such an event in their fake results.
3. Reason mathematically.
Invitation to Learn
Introduce money probability problems.
Instructional Procedures
Curriculum Integration
Girls and boys are born about equally. How does this experiment relate to the
proportion to girls and boys? What are your chances of having either a girl
or a boy? How many children would you need to have to ensure equal numbers of
boys and girls?
Possible Extensions
How many possible outcomes are there when you toss two coins? What are the chances
of getting either a heads or a tails when throwing the dice?
Question: Lauren has 12 coins in her pocket. The probability of her pulling out a penny is 1/2. How many pennies are in her pocket?
Homework & Family Connection
Give students an extra sheet to try this with their parents. Offer extra credit
in math if they do it and bring it signed by their parents.
Jenny claims to have tossed her penny 300 times. The greatest number of either heads or tails in a row is 3. Do you think Jenny actually tossed her coins? Why or why not?