Question

You roll a six-sided die twice. What is the probability of rolling a 2 and then an odd number?

A) 1 /3

B) 1 /6
C) 1/ 12
D) 1/ 18

Answer 1

C) 1/ 12

Explanation:

for a fair 6-sided die, for each independent roll, the possible number of outcomes is 1,2,3,4,5,6. I.e there are 6 possible outcomes

Also realize that there is only one "2" out of the 6 possible outcomes.

hence P(roll 2) = 1/6

Similarly, there are 3 odd numbers (i.e 1, 3, 5) out of the 6 possible outcomes

hence P(roll odd number) = 3 /6 = 1/2

P (roll 2 on first roll then odd number on second roll)

= P(roll 2) x P(roll odd number)

= 1/6 x 1/2

= 1/12