Find the probability that a randomly chosen integer from 1 to 50 is not divisible by either 2 or 3.

First of all, note that there are 50 numbers in total between 1 and 50.

Secondly, every second number is divisible by 2. Therefore, out of 50 numbers, 2 are divisible:

50: 2 = 25 (numbers).

This means that there are still 25 numbers that need to be checked for divisibility by 3.

The first such number is 3, the rest follow at intervals equal to 6 (since we have already crossed out even numbers).

Then all such numbers:

3, 9, 15, 21, 27, 33, 39, 45 – 8 numbers.

Then the probability is:

P = (50 – 25 – 8) / 50 = 0.34.