3 replies to this topic

[jamie bickers]

If you throw a dice once the cance of getting six is 1/6
If you throw a dice twice the cance of getting six is 2/6
If you throw a dice three times the cance of getting six is 3/6
If you throw a dice four times the cance of getting six is 4/6
If you throw a dice five times the cance of getting six is 5/6

Does this mean that if you throw a dice 6 times you are garantied 6?
Of course it doesn't but how come theareticly the chance is 100% when practicly it isn't.

[bonanova]

If you throw a dice once the cance of getting six is 1/6
If you throw a dice twice the cance of getting six is 2/6
If you throw a dice three times the cance of getting six is 3/6
If you throw a dice four times the cance of getting six is 4/6
If you throw a dice five times the cance of getting six is 5/6

Does this mean that if you throw a dice 6 times you are garantied 6?
Of course it doesn't but how come theareticly the chance is 100% when practicly it isn't.

Spoiler for Only your first statement is true.

If you throw two dice there are 36 outcomes.
Of those, only eleven outcomes show a six.
Namely, [16] [26] [36] [46] [56] [66] [65] [64] [63] [62] [61]
Your chances of getting a 6 with two dice are therefore 11/36; not 12/36.

That's the brute force way to analyze, and it will always work for you.
[1] find out how many equally likely ways [N] things could turn out.
[2] count the outcomes [F] that are favorable.
[3] your chances are F/N.

There's an easier way to do this.
Each die has a 5/6 chance of NOT being a six.
Throwing two dice gives you a [5/6][5/6] = 25/36 chance of neither of them being a 6.
The chance that one or both are a 6 is therefore 1-25/36 = 11/36.

What if you throw six dice?
Your chances of getting at least one six are about 2/3.
1-[5/6][5/6][5/6][5/6][5/6][5/6] = 0.6651020233

[spoxjox]

If you throw a dice once the cance of getting six is 1/6
If you throw a dice twice the cance of getting six is 2/6
If you throw a dice three times the cance of getting six is 3/6
If you throw a dice four times the cance of getting six is 4/6
If you throw a dice five times the cance of getting six is 5/6

Does this mean that if you throw a dice 6 times you are garantied 6?
Of course it doesn't but how come theareticly the chance is 100% when practicly it isn't.

Your odds aren't quite right.

If you throw a die (btw, singular is 'die', plural is 'dice') you have a one in six chance of getting a specified number, e.g. six. That means you have five chances in six of not getting a six.

In two dice rolls, your chances of not getting a six are 5/6 for the first roll and 5/6 for the second roll, giving you total odds of (5/6) * (5/6), or 25/36, of not getting a six. Thus, your odds for getting at least one six are one (100% odds) minus the odds of not getting at least one six: 1 - 25/36, or 11/36. Note that this is slightly smaller than 2/6 (= 12/36), as you had said above.

In six dice rolls, your odds of not getting a six are therefore (5/6)^6, or 15625/46656, which is just a bit greater than 1/3 odds. Therefore, your odds of rolling at least one six are one minus this amount, which as a percent is 66.5%.

[caecae]

Ok. well i may not be right but here it goes any way. well i read it a few times and there is a problem because even if you role a die 6 time the prob is going to remain at 1/6 chance for each role but the as you roll the die more times your chance of gettin a six will increase. so i did the math because it was really bugging me and if you roll the dice 6 times it is actually a 40% chance or a 2.4/6 chance of getting a six. i got this from my stat class.