In mathematics exam. a student scored 30% marks in the first paper out of a total of 180. How much should he score in second paper out of a total of 150, If he is to get an overall average of at least 50%?
Correct Answer: 74%
Explanation:
∵ 30% of 180 + N% of 150 = 50% of (180 + 150)
⇒ 54 + (N x 150)/100 = 165
⇒ 3N/2 = 111
∴ N = (111 x 2) / 3 =74
