Hi srepaul,

While applying for IBSAT pplication form you will be asked for the exams through which you want to apply for IBSAt. In the form you need to fill all the required details and in exams you can choose multiple options like CAT/XAT/NMAT etc. In that choose NMAT and enter your score. This way your NMAT score will be taken. 

If you apply from multiple exams, the exam from which your percentile is higher will be considered. 

To apply view this link: https://admissions.ibsindia.org/ibsat2018/registration/