Study the following table and answer the question that follows. A school has four sections A, B, C and D of Class IX students. The results of Science and Mathematics examinations are shown in the following table.

What is the ratio of number of students who failed in Science but passed in Mathematics of section B and section D together to the number of students of section A that passed in both subjects ?

3 : 7

Number of students who failed in Science but passed in Mathematics of section B and section D= 12 + 15 = 27

Number of students of section A that passed in both subjects = 63

required ratio  = 27 : 63

= 3 : 7