The total number of sample points in a sample space of single throw of two dice, n(S)=36 Let E1= Event of getting a sum 7 E2= Event of getting a sum 9 ∴E1={(1,6),(6,1),(2,5),(5,2),(3,4),(4,3)} ⇒n(E1)=6 and E2={(3,6),(6,3),(4,5),(5,4)} ⇒n(E2)=4 ∴P(E1)=