Question

Can some one explain how to solve this?

Answer 1

F or G means list all the stuff that is in F or in G

Answer 2

you should get \(\{5,6,7,9,11,12\}\) first three are in F, second three are in G

Answer 3

as for the second two (they are the same) take the number of elements in F or G (there are evidently 6 of them) and divide by the total number in S, which has 12 elements
you get \(\frac{6}{12}=\frac{1}{2}\)

Answer 4

What about the last part?

Answer 5

it is the same question, so it has the same answer

Answer 6

so 1/2 for both of them?

Answer 7

yes