The answer is: 0.0362
The total number of Master's degree holders = 2848 (from the question)
In order to choose people 40 and above from this Master's degree holder subset,
You choose:
People 40-49 AND People 50 and over.
Number of people 40-49 = 475
Number of people 50 and over = 699
But we also need to take into consideration, the probability of picking a person 40-49 years old OR 50 and over
total Number of people 40 - 49 are 3518
The total Number of people 50 and above are 6518
Thus, we can write the probability as:

The final answer is: 0.0362