Task: Question Answering
Input (English): Problem: a movie buff buys movies on dvd and on blu - ray in a ratio of 17 : 4 . if she returns 4 blu - ray movies , that ratio would change to 9 : 2 . if she buys movies on no other medium , what was the original number of movies purchased ? 
Options: a ) 22 , b ) 28 , c ) 77 , d ) 99 , e ) 378
Output (English): e