Question

Suppose two dice (one red, one green) are rolled. Consider the following events. A: the red die shows 4; B: the numbers add to 5; C: at least one of the numbers is 1; and D: the numbers do not add to 9. Express the given event in symbols.

Either the numbers add to 5, or they add to 9, or at least one of them is 1.
How many elements does it contain?

Answer 1

Supose that each dice have six faces

Part 1

A = {4}

B = {(1,4), (4,1), (2,3), (3,2)}

C = {(1,2), (1,3), (1,4), (1,5), (1,6), (2,1), (3,1), (4,1), (5,1), (6,1)}

D = {(1,1). (1,2), (1,3), (1,4), (1,5), (1,6), (2,1), (2,2), (2,3), (2,4), (2,5), (2,6), (3,1), (3,2), (3,3), (3,4), (3,5), (4,1), (4,2), (4,3), (4,4), (4,6), (5,1), (5,2), (5,3), (5,5), (5,6), (6,1), (6,2), (6,4), (6,5), (6,6)}

Explanation:

I choose solve the part 1.

We use brakets for indicate that the elements belong to a event.

In each event, the first member of each parentheses belong to dice red and the second belong to green dice.

We consider in each event all elements that accomplish the condition.