Question

E B Prutent laut ya ne. Example 3. Suppose you are throwing two fair dice. a) What is the probability that you will roll a sum less than four or bigger than 10? Howy beck b) What is the probability that you will roll doubles or a sum bigger than 10?

Answer 1

Total sample space = 6 * 6 = 36

a) Sample outcome for rolling a sum less than 4 = {(1,1), (1,2), (2,1)}

Sample outcome for rolling a sum bigger than 10 = {(5,6), (6,5), (6,6)}

P(sum less than 4 or bigger than 10) = P(sum less than 4) + P(sum bigger than 10)

                                                           = 3/36 + 3/36

                                                           = 6/36

                                                           = 1/6

b) Sample outcome for rolling doubles = {(1,1), (2,2), (3,3), (4,4), (5,5), (6,6)}

P(rolling doubles or sum bigger than 10) = P(rolling doubles) + P(sum bigger than 10) - P(rolling doubles and sum bigger than 10)

                                                                = 6/36 + 3/36 - 1/36

                                                                = 8/36

                                                                = 2/9