Math/Philsophy bros GTFIH for a simple problem that will blow your mind

Register

Confirm your email

A registration code was sent to your email. Enter it here.

Welcome

You have successfully setup your account.

Forum » Math/Philsophy bros GTFIH for a simple problem that will blow your mind

Results 211 to 212 of 212
Page 8 of 8
First
6
7
8

Thread: Math/Philsophy bros GTFIH for a simple problem that will blow your mind

09-10-2020, 11:04 AM

#211

LuckyAH
Registered User

LuckyAH
Registered User

Join Date: Dec 2016

Age: 36

Posts: 434

Rep Power: 570

The answer is 1/2. The OP says that she is NOT interviewed if it's a wednesday, whereas she IS interviewed if it's a Monday or Tuesday.

So there are two cases:

1) she wakes up and she is interviewed. She knows it must be a Monday or Tuesday. With no other information, she gets asked if the fair coin landed on heads. That's a 1/2 probability.

2) she wakes up and is NOT interviewed. She knows it is a wednesday and she was awoken previously during which time a fair coin was tossed. The chances the coin landed heads is also 1/2.

Either way it's 1/2

09-10-2020, 11:58 AM

#212

Witrebel
Aware since 2004

Witrebel
Aware since 2004

Join Date: Mar 2011

Age: 35

Posts: 1,663

Rep Power: 9198

It's all in the wording. But the fact remains that even if she is wrong 2 times out of 3, the CHANCES of a coin flipping are always 50/50. Most people read the problem wrong and assume it's asking "what are the chances the coin flip was fair" when it is specifically asking her if she thinks it was heads. Given the framework of the problem, she will be WRONG 2/3 of the time. But the coin flip was and always will be 50/50.