Hello Promila,
No, University of Delhi does not conduct any entrance exam for B.Sc Maths (H) admissions. Your best of four subjects of 10+2 or equivalent qualifying exam is used to prepare merit lists and different cutoffs are declared for different colleges of DU.
Yes, St. Stephen's does offer a B.Sc. in Mathematics.
Hope this answers your query, feel free to ask for more info.
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