APCLyingBastard:


Wrong solution and so your answer is flawed.

nairaman66:


A quick one!

There are 5 Stables in a row numbered 1 to 5, in which a horse is hiding. Every night the horse jumps to an adjacent stable, and every morning you have one chance to open a stable to find the horse. How do you solve this game of hide and seek?

emae009:
The OP is correct, the answer to the first test is 1/2 or 50%. Let me simplify it:
1) after eliminating box SS by picking a G ball.
2) you're left with 2 boxes: & GS.
here lies the logic:
3) if you picked the G ball from box , then the probability of picking another G ball is 1 since you're picking from the same box again.
4) if you picked the G ball from box GS, then the probability of picking another G ball is 0 since you're picking from the same box again.
so therefore we have two outcomes; it's either you pick a G ball or you don't pick a G ball so the answer becomes 1/2 or 50%


APCLyingBastard
Sammy07
Nurudeen06

nairaman66:


A quick one!

There are 5 Stables in a row numbered 1 to 5, in which a horse is hiding. Every night the horse jumps to an adjacent stable, and every morning you have one chance to open a stable to find the horse. How do you solve this game of hide and seek?

APCLyingBastard:


[s]On the first night, I put the horse in stable 1.[/s]

Next morning, I check stable 2.

emae009:


1/5.

nairaman66:


Wrong!

GenBuhari:
OP saying my answer is flawed prompted me to look at my solution.
They ate two ways a second consecutive gold could be picked and the probabilities of both options differ, so I calculated probabilities for both option and took an average of the two probabilities to be the probability of picking the second gold ball.

This gave the answer; 5/12 (42%)

BabaRamota1980:


There are 6 balls. You removed one gold ball, that leaves 5 balls. Out of the 5 there are 2 gold. The chance of picking a gold ball is 2/5.


Why u dey play?

APCLyingBastard:
IQ tests need to be mandatory to post here. So I am kicking it off with this very rudimentary test.

Provide reasons for your answer.

See pic below for test.

GenBuhari:
OP saying my answer is flawed prompted me to look at my solution.
They are two ways a second consecutive gold could be picked and the probabilities of both options differ, so I calculated probabilities for both option and took an average of the two probabilities to be the probability of picking the second gold ball .
This gave the answer; 5/12 (42%)

GenBuhari:


may have made error as i did this last calculation mentally.
if first gold ball came from box1 , then Pr of 2nd gold ball would be 1/2
if first gold ball came from box2, then Pr of drawing 2nd gold ball will 1/3

average of the 2 options is 5/12
I believe this must be best solution or answer.

emae009:
The OP is correct, the answer to the first test is 1/2 or 50%. Let me simplify it:
1) after eliminating box SS by picking a G ball.
2) you're left with 2 boxes: & GS.
here lies the logic:
3) [s]if you picked the G ball from box , then the probability of picking another G ball is 1 since you're picking from the same box again[/s]
4) if you picked the G ball from box GS, then the probability of picking another G ball is 0 since you're picking from the same box again.
so therefore we have two outcomes; it's either you pick a G ball or you don't pick a G ball so the answer becomes 1/2 or 50%


APCLyingBastard
Sammy07
Nurudeen06

Edopesin:



The answer is 1/2 but your explanation at 3 is not correct

The probability of picking G again is not 1 cause after eliminating the SS box, one of the remaining two boxes has a S and you don't know if that's what you'll pick next

emae009:


go and read the question again.
"what is the probability of picking a yellow ball from the same box again". same box same box same box same box same box you drew the first ball from

Edopesin:


Think!!

You don't know if the other ball in that same box is silver so the probability is not 1

it's either another yellow or a silver

emae009:


Step by step:
1) there are now 2 boxes right. (we can agree on that front).
you have picked a gold ball from a box which is either the box or the GS box.
now answer this question: if it's the box that you picked the first gold ball from and your asked to pick another ball from that same box. what is the probability that it'll be a gold ball?

Edopesin:


The probability that it will be a gold ball is not 1 and that's why the answer is 1/2

how you don't get it is a mystery

emae009:


did you even read my first explanation, the one you quoted very well. the answer is 1/2. I was explaining why it's 1/2 in a simple way. the OP did the same thing in a graphical method. the answer is not 1/2 because you choose the first ball from the GS box, it's half because since you don't know which of the two boxes you chose the first ball from, it means your second ball can be either a G ball or a S ball giving you the probability of 1/2.

Edopesin:


You just repeated what I've been saying since

good luck ✌️

emae009:

read well before you quote people...