Answer & Solution
Answer: Option D
Solution:
Number of students opting Mathematics in 2005 and 2008
= 15000 + 30000
= 45000
Number of students opting for these three subjects in 2005 and 2008
= {(5 + 35 + 15) + (25 + 30 + 30)} thousands
= 55000 + 85000
= 140000
$$\eqalign{
& \text{Required %} \cr
& = \left(\frac{45000}{140000}\times100\right)\% \cr
& = \frac{225}{7}\% \cr
& = 32.14\% \cr
& \approx 32\% \cr} $$