There are 120 students in a class. Some of them read Maths, History, or…
2022
There are 120 students in a class. Some of them read Maths, History, or English. Initially, no student reads all three subjects.
The known groups are: 24 read only Maths and History, 8 read only History and English, 21 read only Maths and English, 32 read only Maths, 13 read only History, and 17 read only English.
If 9 students who read only Maths start reading all three subjects, find the percentage of students who read History.
- A.
50%
- B.
60%
- C.
40%
- D.
None of these
Attempted by 39 students.
Show answer & explanation
Correct answer: D
Check the listed groups: 32 + 13 + 17 + 24 + 8 + 21 = 115. Since the class strength is 120, 5 students are outside these listed subject groups.
Initial History readers: Only History + only Maths & History + only History & English = 13 + 24 + 8 = 45.
After the change: 9 students from only Maths start reading all three subjects, so they also become History readers.
New History total = 45 + 9 = 54.
Percentage = (54 / 120) x 100 = 45%.
Final answer: 45% is not listed, so option D, None of these, is correct.