If I role two dice, their sum is most likely 7. So if I role a 2 with one die, is the next roll most likely to be a 5?

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Seems weird any way I think about it. Thanks!

In: Mathematics

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Anonymous 0 Comments

If you want to get 7, there’s always hope after the first roll. No matter what the first roll is, there’s one face you could roll on the second that would add up to 7.

If you’re targeting a number larger than 7, there are some rolls of the first die that will leave you hopeless:

– If you want to get 8, it’s hopeless if the first roll is 1.
– If you want to get 9, it’s hopeless if the first roll is 1-2.
– If you want to get 10, it’s hopeless if the first roll is 1-3.
– If you want to get 11, it’s hopeless if the first roll is 1-4.
– If you want to get 12, it’s hopeless if the first roll is 1-5.

Likewise if you’re targeting a number smaller than 7, you could make your target or overshoot it on the first roll, and the second roll will always add at least 1:

– If you want to get 6, it’s hopeless if the first roll is 6.
– If you want to get 5, it’s hopeless if the first roll is 5-6.
– If you want to get 4, it’s hopeless if the first roll is 4-6.
– If you want to get 3, it’s hopeless if the first roll is 3-6.
– If you want to get 2, it’s hopeless if the first roll is 2-6.

That’s why totals other than 7 are less likely:
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