John and Mike were offered mints. What is the probability that at least John or Mike would respond favorably? (Hint: Use the classical definition).
A) $ \frac{1}{8} $
B) $ \frac{1}{2} $
C) $ \frac{3}{4} $
D) $ \frac{3}{8} $

Question

John and Mike were offered mints. What is the probability that at least John or Mike would respond favorably? (Hint: Use the classical definition). 
A) $ \frac{1}{8} $
B) $ \frac{1}{2} $
C) $ \frac{3}{4} $
D) $ \frac{3}{8} $

Quizplus · Accepted Answer

The classical definition of probability states that number of favorable outcomes divided by the total number of possible outcomes. In this case, there are two possible outcomes, either John or Mike responds favorably or they both respond unfavorably. Since we know that they were both offered mints, there are four equally likely outcomes (John says yes, Mike says yes; John says no, Mike says yes; John says yes, Mike says no; John says no, Mike says no). Of these four outcomes, three are favorable (the first three listed above) and one is unfavorable (both say no). Therefore, the probability is 3/4.

John and Mike Were Offered Mints 18 \frac{1}{8} 81​ B) 12 \frac{1}{2} 21​

John and Mike Were Offered Mints $\frac{1}{8}$ B) $\frac{1}{2}$