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प्रश्न
80% of students in a class took Statistics and 45% took Mathematics. If each student took Statistics or Mathematics and 40 took both, the total number of students in the class was:
पर्याय
160
180
200
225
उत्तर
160
Explanation:
Let the total number of student in the class is 100
Number of students took statistics = 80
Number of students took Mathematics = 45
Now, the number of students took both subjects
= 80 + 45 − 100 = 25
∴ When 25 students took both subjects,
then the total number of students = 100
∴ When 40 students took both subjects, then
total number of students`=100/25xx40=160`
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