A students was awarded certain marks in an examination. However, after re-evaluation, his marks were reduced by 40% of the marks that were originally awards to him, so that the new score now became 96. How many marks did the student lose after re-evaluation?

Let a student was awarded in exam = N marks
According to the question,
After re-evaluation his score
⇒ N - N x (40/100) = 96
⇒ N - 2N/5 = 96
⇒ 5N - 2N/5 = 96
⇒ 3N/5 = 96
⇒ N = (5 x 96)/3 = 5 x 32
⇒ N = 160
So, a student was awarded by 160 marks in examination
∴ Reduced marks after re-evaluation = 160 - 96 = 64