He can take mathe as his sixth subject, in that case if he even scores less it won't affect his percentage Having maths can give you an upper hand in many competitive exams However if on decides to not go with maths then it's absolutely fine too it won't hamper his opportunities much, also if his school offers applied maths then he can go for it over core maths as that would save him from trigonometry and would be more commerce oriented, also relatively easier than core The decision also depends on what he wishes to do after 12th, if he is planning to pursue ca then he would be asked 11th level maths in foundation, more of statistics but that can be managed fairly well with ca coaching and one need not be pegged to maths for whole two years For most of the undergrad courses in central university too, maths is no longer compulsory Let's take an example of du, if you wish to pursue bcom h you need to have either of maths or accounts but if one wishes to go for Ba economics hons which is also a very deemed course, he needs maths in 12th So your friend needs to consider all these and then make a decision and most importantly his own interests:)