Rohan scored twice as many marks in English as he did in Science. His total marks in English, Science and Mathematics are 126. If the ratio of his marks in English and Mathematics is 2: 3, his marks in English are:

42

Science : English : Mathematics 

     1     :     2

                  2      :      3

___________________________

     1     :     2      :      3              ⇒  Total = 6R = 126

                                                                  R = 21

Rohan's marks in English = 2R = 2 x 21 = 42