Here, Number of students who know Hindi,`n(A) = 100`
Number of students who know English,`n(A) = 50`
Number of students who know both languages,`n(AnnB) = 25`
As each of the students knows either Hindi or English, total number of students will be `n(AuuB)`.
We know,
`n(AuuB) = n(A)+n(B)-n(AnnB) = 100+50-25 = 125
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