Question

Two dice are rolled, find the probability that the sum is equal to 4
 

Answer 1

Sample space (S) = {(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) (3, 6) (4, 1) (4, 2) (4, 3) (4, 4) (4, 5) (4, 6) (5, 1) (5, 2) (5, 3) (5, 4) (5, 5) (5, 6) (6, 1) (6, 2) (6, 3) (6, 4) (6, 5) (6, 6)}

n(S) = 36

Let E₂ be the event of getting the sum is equal to 4

E₂ = {(1, 3) (2, 2) (3, 1)}

n(E₂) = 3

p(E₂) = `("n"("E"_2))/("n"("S"))`

= `3/36`

= `1/12`