+0  
 
0
58
3
avatar+58 

A simulated game of chess is programmed between two computers. The game is supposed to be biased in favor of player B winning 4 out of 5 times. Which is the most suspicious set of outcomes of 30 games played between the two computers?

A.

AABABBBABBBBBBBBABBBABBBBBBBBA

B.

ABBABBAABBBBBABBBBBBBBBBBBBABB

C.

ABBABABABABBABABABABABABABABAA

D.

 ABBABBBABBBBBBBBABBBABBBBBBBBB

spirit1  Nov 9, 2018
 #1
avatar+114 
+2

Let's see all of them.

 

It seems like for all of them B overpowers, except for C.

A, B, D have mostly B's but C has a general mix, therefore, the answer is C.

 

You are very welcome!

:P

CoolStuffYT  Nov 9, 2018
 #2
avatar+2793 
+2

CoolStuffYT is correct but here's a more rigorous analysis

 

Rom  Nov 9, 2018
 #3
avatar+27139 
+2

A slightly simpler way of looking at this is to note that the expected number of games won by B is (4/5)*30 = 24.

 

Number of games apparently won by B: 

A:   23

B:   24

C:  15

D:  25

 

Clearly C is suspicious!

Alan  Nov 9, 2018

27 Online Users

avatar

New Privacy Policy

We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive information about your use of our website.
For more information: our cookie policy and privacy policy.