a pair of dice are tossed, determine the probability that at least one of the two dice shows a 1. Can someone please show me how to solve this.

Question

cwrw238 · Answer

since there are 6 sides to a dice the probability of throwing 1 is 1/6 and probability of not throwing a 1 is 5/6
when throwing 2 dice the possiblities for 'at least one 1' are

(1)  1 and not 1
or  (2)  not 1 and 1
or  (3)  1 and 1

probability for (1) = 1/6 * 5/6 =  5/36
                        (2) = 5/6 * 1/6 =  5/36
                        (3) = 1/6 * 1/6 = 1/36
adding required probability =
  5/36 + 5/36 + 1/36 = 11/36

cwrw238 · Answer

a tree diagram illustrates this:

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