What is the greatest prime factor of (11! × 10!  + 10! × 9!)/111?	Choose the correct option
A) 2 B) 3 C) 5 D) 7 E) 11

Rationale: ( 11 ! × 10 !   + 10 ! × 9 ! ) / 111 in numerator take out 10 ! * 9 ! as common term 10 ! ∗ 9 ! ( 11 × 10   + 1 ) / 111 10 ! ∗ 9 ! ∗ 111 / 111 10 ! ∗ 9 ! 10 ! has 7 as the greatest prime factor , so ans is 7 answer : d
Answer: D