greetings varada,
no you will not face any reduction in percentage in du application.
your final marks will be counted as your actual marks and so your final marks will be considered for admission.
grace marks are mentioned in the mark sheet but do not affect the cut-off.
pls refer to the previous year cut-off for du:
http://du.ac.in/cut-off.html
more more information, visit,
http://du.ac.in/adm2019/
hope this helps.
good luck.
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