In an examination a pupil's average marks were 63 per paper. If he had obtained 20 more marks for his Geography paper and 2 more marks for his History paper, his average per paper would have been 65. How many papers were there in the examination?  Options.
A) 10  B) 11  C) 8  D) 9  E) 12
Let the number of papers be x. Then,   63x + 20 + 2 = 65x   = 2x = 22   = x = 11.   ANSWER 11
<result>B</result>
In an examination a pupil's average marks were 63 per paper. If he had obtained 20 more marks for his Geography paper and 2 more marks for his History paper, his average per paper would have been 65. How many papers were there in the examination?