JEE Advanced 2021 Full Test 2 Paper 2

10 IIT students T1,T2,.........T10 can be arranged in 10! ways. Now the number of ways in which two PET student can be placed will be equal to the number of ways in which 3 consecutive IIT students can be taken i.e. in 8 ways and can be arranged in two ways P(10!)(8)(2!).
Alternatively 3 IIT students can be selected in ‌10C3 ways. Now each selection of 3 IIT and 2 PET students in P1T1T2T3P2 can be arranged in (2 !) (3 !) ways. Call this box X. Now this X and the remaining IIT students can be arranged in 8! ways
⇒ Total ways ‌10C3(2!)(3!)(8!)]