First of all congratulations to your son for such a fantastic score!!

Your son's academic records are average which could create a little problem as After CAT exam every college in which you have applied prepares a merit list to call students for next round of interview based on your aggregate score which comprises of many parameters such as CAT marks, 10th, 12th and graduation percentage, work experience, engineer or non-engineer whose weightage varies for all different colleges.

In this academic marks, weightage is around 10-25% this could bring your son's aggregate score down and hamper the merit rank. But this will mostly be a problem for getting calls from old IIMs like IIM L, K, I and S.

Your son will definitely get calls from most of the new IIMs and ultra new IIMs including IIM Rohtak. So he should focus on preparing the second round of WSAT and interview because that is very crucial for converting your call.

All the best for your son!!

Hi Rajendra , 

Congrats to your Son for scoring such a good score, For getting admission In IIM Rohtak there is minimum eligiblity criteria which is mentioned on link which u can click 

http://www.careerlauncher.com/cat-mba/bschools-eligibility/iim-rohtak-eligibility.html

However list says that in 10  Candidate should have 70% in General category , but howwver u can take call of getting chance 

best of luck