(ii) A die is thrown :
P is the event of getting an odd number.
Q is the event of getting an even number.
R is the event of getting a prime number.
Sol. When a die is thrown
S = { 1, 2, 3, 4, 5, 6 }
n (S) = 6
P is the event of getting an odd number
P = { 1, 3, 5 }
∴ n (P) = 3
Q is the event of getting an even number
Q = { 2, 4, 6 }
∴ n (Q) = 3
R is the event of getting a prime number
R = { 2, 3, 5 }
∴ n (R) = 3
Here P ∩ Q = ϕ and P U Q = S
∴ P and Q are complementary events.
