The first step to solving probability problems is identifying the total number of outcomes. In this case, we have eight cards labeled from P to W. So, the total number of outcomes is 8.
Next, we determine the number of favorable outcomes. Here, we are only interested in selecting card P, Q, or R. Hence, there are 3 favorable outcomes.
Probability refers to the number of ways a specific event can occur divided by the total number of outcomes. It's calculated using the formula:
P(A) = Number of favorable outcomes / Total number of outcomes
In our case, the number of favorable outcomes is 3 (the cards P, Q, and R), and the total number of outcomes is 8 (cards from P to W).
Therefore, the probability P(A) = 3 / 8 = 0.375 in decimal form.
So the probability of choosing a letter from P to R from the box is 0.375. If you want your answer in fraction form, the simplest form would be 3/8.