Let S 5 7 13 be a sample space associated with an experimen

Let S = {5, 7, 13} be a sample space associated with an experiment.

(a) List all events of this experiment.

(b) How many subsets of S contain the number 13?

(c) How many subsets of S contain the number 7 or the number 13?

Solution

a) The events in S are [ { 5}, {7}, { 13}, { 5, 7}, { 5,13}, { 7, 13}, { 5, 7, 13} ]

b) The subsets { 13}, { 5,13}, {7, 13} and { 5, 7, 13} contain 13 i.e. 4 subsets of S contain 13.

c) The subsets { 7}, { 5,7}, { 7,13} and { 5, 7, 13} contain 7. The subsets { 7}, {13},{ 5,7},{5,13} contain the number 7 or the number 13 i.e. 4 subsets contain the number 7 or the number 13.