probability

[zriceman]

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destroyer 103: Two numbers between 1 and 30 inclusive are drawn in a contest. What is the probability that both numbers are even?

Solution states probability of drawing an even number is 15/30. Shouldn't it be 15/31 since its 1 to 30 INCLUSIVE?

 

[Streetwolf]

Why don't you go and count the #s between 1 and 30 🙂

 

[zriceman]

haha oops

 

[ramin123]

Why is the answer not 1/2 * 14/29= 7/29?? I thought you have to pick one number and then pick the next number.

 

[DentalDeac]

Why is the answer not 1/2 * 14/29= 7/29?? I thought you have to pick one number and then pick the next number.

Yeah, I don't understand why your method doesn't work...

It would seem that the first choice you have a 15/30 chance of getting an even number (1/2) and the second choice you would have a 14/29 chance of picking an even number so it should be 7/29

 

[ramin123]

Streetwolf-- where are you?

 

[theedaddy77]

yo i actually counted the numbers even between 1-30, NOT INCLUDING 30 and got 14/30 so 7/15?

 

[Streetwolf]

Yeah so he never said anything about the answer, he just was wondering why the probability of picking the first even # is 15/30. He made a mistake and thought that there were 31 numbers between 1 and 30.

If you did the problem it would be 15/30 * 14/29.

To the poster above me, the problem says inclusive which means you count the numbers 1 and 30.

 

[Hugh Mannity]

What would the terminology be to not include 1 and 30, exclusive?