Task: Question Answering
Input (English): Problem: 12 buckets of water fill a tank when the capacity of each bucket is 81 litres . how many buckets will be needed to fill the same tank , if the capacity of each bucket is 9 litres ? 
Options: a ) 96 , b ) 110 , c ) 100 , d ) 90 , e ) 108
Output (English): e