Solution

Solution:

Let’s break down the problem step by step:

• Total number of software professionals: 40
• Number of professionals who knew PYTHON: 25
• Number of professionals who knew JAVA: 20
• Number of professionals who knew neither language: 7

So, the number of professionals who knew either PYTHON or JAVA or both is: 40 - 7 = 33

Now, let’s use the formula for the union of two sets:
\(\text{Number of people who know PYTHON or JAVA} = \text{Number of people who know PYTHON} + \text{Number of people who know JAVA} - \text{Number of people who know both languages} \)
Substitute the known values:
\(33 = 25 + 20 - \text{Number of people who know both languages} \)
\(33 = 45 - \text{Number of people who know both languages}\)
\(\text{Number of people who know both languages} = 45 - 33 = 12\)

Mistake Points

Thus, the number of people who knew both languages is 12, but  In official question 12 is not listed in option.