Yes , i had understand yoyr query regarding the isc board as i would like to give you brief about this as follows:

AnswerYes, you can appear for the ISC Examination in the subject Mathematics. ... You will have to give a written application to the Principal of the School from where you wish to appear for the ISC Examination, whowill register you online for the entry to theExamination.

The passing mark for ICSE is 35 in each subject and for ISC it is 40. A student must pass in English and any other 4 subjects for ICSE and English and 3 subjects for ISC. No everyone don't pass. ... it is very difficult to fail in ISC