This month’s math puzzle is really more of an exploration. Here are some activities to try. They require collecting lots of data so they are good to do with your whole class or even your whole school.

• Pick up a book near you. Open the book to a random page and record the page number. Pick up a different book and flip to another random page. Record the first digit of that page. Try this with many different books until you have recorded 100 page numbers or more.
• In a store, record the prices of 100 or more items. It doesn’t matter what kind of store it is. You can also do this by going to a web site that sells things and record the prices of the various items they offer.
• Get the street addresses of everyone in your class. Have them write down the addresses of other people they know until you have 100 or more addresses.
• Find out the populations of the 100 or more largest cities and towns in your country. Write these down.

For each set of data some numbers have 1 as the first digit, some have 2, some begin with 3, and so on. Do you think all the digits from 1 through 9 have about an equal chance of occurring or does one of the digits appears more often?

Now total up how many times each digit occurs in each data set. Are you surprised? Do you have an explanation for what you found?

Try your luck, then check our solution.

This math exploration was suggested by Lawrence Lee.