The two events described in this exercise are tossing a penny and rolling a number cube. Neither of these events affects the probability of the other so these are independent events. If two events are independent, then the probability of both occurring is the product of their individual probabilities.
P(AandB)=P(A)* P(B)
Here, A is tossing tails and B is rolling 3. Let's start by calculating the probability of the coin landing on tails.
P(A)&=1/2 l←heads on a tails ←possible outcomes
Let's now find the probability of rolling 3.
P(B)&=1/6 l← 3on a number cube ←possible outcomes
Finally, we multiply P(A) and P(B).
