Question

Difficulty: EasyLogical Venn Diagrams

In a technology seminar attended by 6060 software engineers, 3535 engineers know Python and 2525 engineers know Java. If 1010 engineers know both Python and Java, how many engineers know neither of these two programming languages?

Answer: 10 engineers

Answer

The number of engineers who know neither Python nor Java is 10.
The correct answer is 10. By taking the sum of Python knowers (3535) and Java knowers (2525) and subtracting those who know both (1010), we obtain 5050 engineers who know at least one language. Subtracting this from the total 6060 seminar participants leaves 1010 engineers who know neither language.

Step-by-Step Solution

1
Find the total number of engineers who know at least one programming language
50 engineers know at least one language
Apply the two-set union formula: n(AB)=n(A)+n(B)n(AB)=35+2510=50n(A \cup B) = n(A) + n(B) - n(A \cap B) = 35 + 25 - 10 = 50.
2
Calculate the number of engineers who know neither language
10 engineers know neither language
Subtract the number of engineers knowing at least one language from the total group size: 6050=1060 - 50 = 10.

Key Concept

Two-Set Inclusion-Exclusion Principle and Complement of Sets
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