Hey,

In order to calculate your best four percentage for bsc maths hons you need to include one language subject, maths (necessarily) and any two elective subjects as provided by the du. Also you need to fetch atleast 50% marks in your maths subject in order to seek admission in maths hons.

Following are the elective/academic subjects you  may include in your best four score -

Arabic

Music

German

Bengali

Philosophy

Hindi

Botany

Political Science

History

Biology/Biotechnology

Accountancy

Urdu

Chemistry

Punjabi

Home Science

Commerce/Business Studies

Sociology

Italian

Computer Science/Informatics Practices

Statistics

Mathematics

Economics

Zoology

Persian

English

French

Physics

Legal Studies

Geography

Psychology

Spanish

Geology

Sanskrit

Any other subject included in best apart from the list above will lead to a deduction of 2.5% from your best four percentage . Eevn including physical education will lead you a deduction of 2.5% from your best four percentage .

Hope this helps. 

Good luck!