Hi Sangeetamaeena!

The cutoff for 2018 for Dr Sampurnanand Medical college under state quota for your category was 441 while in 2017 it was 405. I would say that your brother has a 50-50 chance of getting a seat. 

To know more about cutoffs of Rajasthan, visit this link: https://www.medicine.careers360.com/articles/neet-cutoff-rajasthan/amp

You can also use our online predictor tool to know which colleges your brother might get based on his NEET scores, follow this link to know more: https://medicine.careers360.com/neet-college-predictor?icn=NEET_clgpd&ici=sticky-qna-wap

Good luck!