Flip a coin to learn about probability!

“Probability” is how likely something is to take place.

You may know that if you flip a coin, half of the time it comes up heads and half of the time tails.


What if we decide to flip a coin twice? What are the chances that it will come up heads both times? Click here to see the answer.



If we flip a coin 3 times, what are the chances that it will come up heads all 3 times? Click here to see the answer.




*You can keep adding more flips and for each additional flip, it will become ½ as likely as the previous time.  The important thing to remember is that when you figure out how likely it is for separate events (several coin flips) to happen in a row, you have to multiply the chances of each event happening alone (a single coin flip).


You can test these answers by flipping coins in sets of 1 or 2 or 4 or 8 flips and keeping track of the results.  The more sets of flips you do, the more likely your results will approach the actual probabilities.




  Fun Facts About Money

1. Has a woman's portrait ever appeared on U.S. paper money?

Martha Washington is the only woman whose portrait has appeared on a U.S. currency note.  It appeared on the face of the $1 Silver Certificate of 1886 and 1891 and the back of the $1 Silver Certificate of 1896.


2. In 2010, how many U.S. currency bills were delivered by the Bureau of Engraving and Printing?

6,400,000,000 or 6.4 billion!  This is about 1 bill for every person on the earth.


3. What was the average cost of producing these bills in 2010?

It cost 9.6 cents per note (or less than a dime each).


4. How much ink was used per day to print bills at the Fort Worth, Texas and Washington D.C. facilities?

It took 9 tons of ink or 18,000 pounds.  This is approximately the weight of 6 average sized cars!


Source: U.S. Treasury, Bureau of Engraving and Printing



  U.S. Currency


Have you ever wondered how long U.S. paper money lasts?

Bills that get worn out from everyday use are taken out of circulation and replaced.


Try to match the denomination of bill with how long it lasts on average.



 Lifespan in months














Click here for the answers!


Source: U.S. Treasury, U.S. Bureau of Engraving and Printing


 Click here to view previous Money Basics for Kids!