Dear aspirant,

To score a minimum of 300 marks, you'll have to get a 100 questions right and then no wrong answers. Given this situation, you'll have to minimize the number of wrong answers you get. For this, you'll have to attempt a minimum of 120 - 110 questions out of 130 given that 30 percent of your answers are wrong.

120 * 0.3 = 36   ................. 360-36 = 324

110 * 0.3 = 33 ................... 330 - 33= 297

Hope this helps