Question

Let an integer be chosen at random from the integers 1 to 30 inclusive. Find the probability that the integer chosen is divisible by 3.
a. 9/30
b. 11/30
c. 1/3

Answer 1

There are a total of 30 integers and 10 of these are divisible by 3 (3, 6, 9, 12, 15, 18, 21, 24, 27, and 30). So the probability of getting an integer divisible by 3 is $\frac{10}{30}$ = 1/3. The answer is letter C.