Given that a vending machine dispense gumballs in a regularly repeating cycle of ten different colors, if a quarter buy 3 gumballs, what is the minimum amount of money that must be spent before 3 gumballs of the same color are dispensed?作者: scott_umac 时间: 2009-11-4 02:07:48
I think this is not a problem on Probability. Vending machine dispense gumballs in a regularly repeating cycle, not randomly。
You have to buy at least 21 gumballs before 3 gumballs of the same color are dispensed。
*#########*#########*
* stands for the color, # stands for other colors.
Which is 21/3= 7 quarters
If I am wrong, please correct me.作者: tianrunhe 时间: 2009-11-4 02:10:05