While preparing for a management entrance examination Romit attempted to solve three paper, namely Mathematics, Verbal English and Logical Analysis, each of which have the full marks of 100. It is observed that one-third of the marks obtained by Romit in Logical Analysis is greater than half of his marks obtained in Verbal English By 5. He has obtained a total of 210 marks in the examination and 70 marks in Mathematics. What is the difference between the marks obtained by him in Mathematics and Verbal English?

Let 'a' and 'b' be the marks obtained by Romit in Verbal English and Logical Analysis respectively. It is given that,

a + b + 70 = 210

a + b = 140.  ... (1) 

It is observed that one-third of the marks obtained by Romit in Logical Analysis is greater than half of his marks obtained in Verbal English By 5.

$$\dfrac{b}{3} - \dfrac{a}{2} = 5$$

$$2b - 3a = 30$$   ... (2)

On solving equation (1) and (2) we get b = 90 and a = 50. 

  Hence, the difference between the marks obtained by him in Mathematics and Verbal English = 70 - 50 = 20.

Therefore, option C is the correct answer.