Task: Question Answering
Input (English): Problem: if john makes a contribution to a charity fund at school , the average contribution size will increase by 50 % reaching $ 75 per person . if there were 4 other contributions made before john ' s , what is the size of his donation ? 
Options: a ) $ 100 , b ) $ 175 , c ) $ 200 , d ) $ 250 , e ) $ 450
Output (English): b