# Math

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If two number cubes are tossed, what is the probability of getting a sum that is less than 6, given that 1 number cube shows a 3 ?

• Math -

Assuming 6-sided number cubes.

Let the events
A=throwing less than 6
B=one of them is a three

Then P(A∩B)
=|{(1,3),(2,3),(3,1),(3,2)}| / 36
= 1/9

P(B)
=2/6
=1/3

Throwing less than six given one of them is a 3 is therefore the conditional probability of A given B, or
P(A|B)
=P(A∩B)/P(B)
=(1/9) /(1/3)
=1/3

• Math -

I have a different one so i don't know this one sorry!!

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