roll of the die

zoso · #1 $Old$ July 18th, 2006, 09:17 PM

Even number = that number is added to your score

Odd number = that number subtracted from your score

What is the expected value of a single roll of the die, and how is it calculated?

Quick · #2 $Old$ July 18th, 2006, 09:25 PM

Quote:

Originally Posted by zoso

Even number = that number is added to your score

Odd number = that number subtracted from your score

What is the expected value of a single roll of the die, and how is it calculated?

Tell me, what is the average score of all the possible outcomes?

I'll show you...

note: $s_1$ is the amount of points you'll get when you roll a 1

average is:

$\frac{s_1+s_2+s_3+s_4+s_5+s_6}{6}=\frac{\neg1+2-3+4-5+6}{6}=\frac{3}{6}=\boxed{\frac{1}{2}}$

and that is the expected outcome for a single roll of the die. Yes I know it's impossible to get that number with a die, but that's the best math has to offer.

malaygoel · #3 $Old$ July 18th, 2006, 09:26 PM

Quote:

Originally Posted by zoso

Even number = that number is added to your score

Odd number = that number subtracted from your score

What is the expected value of a single roll of the die, and how is it calculated?

Expected value of a single roll of dice is 3.5

Malay

Quick · #4 $Old$ July 18th, 2006, 09:31 PM

Quote:

Originally Posted by malaygoel

Expected value of a single roll of dice is 3.5

Malay

oooooh, conflict. How would you find 3.5 as an answer if that is higher than the expected outcome if all numbers counted as positive?

malaygoel · #5 $Old$ July 18th, 2006, 09:40 PM

Quote:

Originally Posted by Quick

oooooh, conflict. How would you find 3.5 as an answer if that is higher than the expected outcome if all numbers counted as positive?

There are six numbers and the probability of any one of them is 1/6.
Hence expected value= $\frac{1}{6}.1 + \frac{1}{6}.2 + \frac{1}{6}.3 + \frac{1}{6}.4 + \frac{1}{6}.5 + \frac{1}{6}.6$

Malay

zoso · #6 $Old$ July 18th, 2006, 09:41 PM

Quote:

Originally Posted by Quick

Tell me, what is the average score of all the possible outcomes?

I'll show you...

note: $s_1$ is the amount of points you'll get when you roll a 1

average is:

$\frac{s_1+s_2+s_3+s_4+s_5+s_6}{6}=\frac{\neg1+2-3+4-5+6}{6}=\frac{3}{6}=\boxed{\frac{1}{2}}$

and that is the expected outcome for a single roll of the die. Yes I know it's impossible to get that number with a die, but that's the best math has to offer.

blatantly simple, I really need to think more

Quick · #7 $Old$ July 18th, 2006, 09:43 PM

Quote:

Originally Posted by malaygoel

There are six numbers and the probability of any one of them is 1/6.
Hence expected value= $\frac{1}{6}.1 + \frac{1}{6}.2 + \frac{1}{6}.3 + \frac{1}{6}.4 + \frac{1}{6}.5 + \frac{1}{6}.6$

Malay

You didn't read the entire question, if the number is odd, than it's subtracted from the score.

malaygoel · #8 $Old$ July 18th, 2006, 09:46 PM

Quote:

Originally Posted by Quick

You didn't read the entire question, if the number is odd, than it's subtracted from the score.

Sorry
Yes, if it is to be subtracted. then the answer is 0.5.

Malay

malaygoel · #9 $Old$ July 18th, 2006, 09:48 PM

Quote:

Originally Posted by zoso

blatantly simple, I really need to think more

You are correct here.
Extend it.
Try for double throw of dice.

Malay