Task: Question Answering
Input (English): Problem: a bag contains 10 green and 8 white balls . if two balls are drawn simultaneously , the probability that both are of the same colour is 
Options: a ) 8 / 15 , b ) 21 / 44 , c ) 3 / 5 , d ) 11 / 15 , e ) 7 / 15
Output (English): b