The  McGraw Hill 6th grade book series of games. 
 Instructions: 
Find three coins of different sizes (e.g. quarter, nickle, penny). 
Flip each and record the head/tail value. 
Look up 
 a number in Door A
. Flip the three coins and do a look up in 
 a number in Door B
.  
Multiply them
. Your opponent may challenge you. 
Look up the answer in the table on the next page. 
If you are right and your opponent didn't challenge you, you get a point. 
If you are right and your opponent did challenge you, you get two points. 
If you are wrong and your opponent challenged you, 
your opponent gets a point. 
If you are wrong and your opponent didn't challenge you, nobody gets a point. 
Your opponent plays next.
 vals[0] | DecimalMult | | Coin tosses (largest to smallest): | TTT | TTH | THT | THH | HTT | HTH | HHT | HHH | 
| Door A | 0.2 | 0.02 | 2 | 0.04 | 0.4 | 4 | 0.05 | 0.5 | 
| Door B | 0.3 | 0.03 | 3 | 0.4 | 4 | 0.04 | 0.2 | 0.02 | 
   On a different page so the players have to turn to it...