In an examination students fail in Mathematics, fail in English. If fail in both, the pass percentage is:
- A
- B
- C
- D
Solution & Step-by-step Explanation
Let's apply the principle of inclusion-exclusion for sets to find the total percentage of students who failed in at least one subject.
Let:
* be the percentage of students failing in Mathematics =
* be the percentage of students failing in English =
* be the percentage of students failing in both subjects =
The total percentage of students who failed () is:
The percentage of students who passed all subjects is the complement of the total fail percentage:
Let:
* be the percentage of students failing in Mathematics =
* be the percentage of students failing in English =
* be the percentage of students failing in both subjects =
The total percentage of students who failed () is:
The percentage of students who passed all subjects is the complement of the total fail percentage: