Hi Nandini,

All the details are compiled in an article here about NATA Exam 2018. Please give it a good read to get a gist on the same. Kindly refer the link provided below:

https://engineering.careers360.com/articles/nata
 

For a quick glance specific to your question:

Candidates will be considered as qualified in NATA 2018 only if he or she fulfils all three conditions mentioned below:

• Minimum 25% must be secured in MCQ portion (30 out of 120) 
• Minimum 25% must be secured in Drawing portion (20 out of 80)
• Overall qualifying marks (out of 200) would be based on post-exam statistics and at the discretion of the Council.

All the best.