problem prime time

Started by
1 comment, last by frob 9 years, 5 months ago

A man has a bag full of balls

the number of balls inside the bag is unknown

each ball is marked with a different number

the number is represented in binary

he tells me that there are two different special balls inside the bag, ball "a" and ball "b"

I take one ball out of the bag, ball "c" and give it to him

he tells me

that if ball "c" number is equal to ball "a" he gives me a million dollars

but if ball "c" number is equal to ball "b" I have to give him a million dollars

he knows and tells me

that ball "a" binary number starts with two off bits, 00XXXXX..... and

that ball "b" binary number starts with one off bit , 0XXXXXX.....

now he takes a look at ball "c" and tells me that it's binary number starts with one off bit , 0XXXXXX.....

what is the probability of winning and losing?

Advertisement

Smells too much like homework.

Sorry, please do your own homework. It is how you learn.

Thanks for sharing a fun little math problem, and those who want to do it I'm sure will enjoy it.

Also, Google shows this as strikingly similar to a problem in the book "Introduction to Probability" by Grinstead and Snell.

This topic is closed to new replies.

Advertisement