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Explanation: Total no. of student=150
None / neither English nor Telugu=30
No. of Students who speak only one or both=(150-30)=120
=> 120 students can speak english or telugu or both.
No. of Students speak only English= [120-85(telugu)]=35
No. of students speak only Telugu= (120-55) = 65
Remaining 120-(65+35)=20 students can speak both.