Question

juan rolls a fair number cube twice what is the probability that he will roll an odd number on the first roll and an even number in second

Answer 1

1/4

Explanation:

`\mathsf{Probability \ of \ an \ event \ occurring = (Number \ of \ ways \ it \ can \ occur)/(Total \ number \ of \ outcomes)}`

Assuming the number cube has faces number 1 through 6, the probability of rolling any of the number is 1/6.

Therefore,

P(odd number) = P(1) or P(3) or P(5)

= 1/6 + 1/6 + 1/6

= 3/6

= 1/2

Similarly,

P(even number) = P(2) or P(4) or P(6)

= 1/6 + 1/6 + 1/6

= 3/6

= 1/2

⇒ P(odd) AND P(even) = 1/2 × 1/2 = 1/4