The 4th observation also gives the same result (i.e. 1.5). Then kindly let me know why are we choosing the 1st observation.

Asked by mrinalini mrinalini | 28th Feb, 2015, 09:32: PM

Expert Answer:

According to the fourth observation,
 begin mathsize 12px style angle straight i space equals space 60 degree space and space angle space straight r space equals space 40 degree Therefore comma space fraction numerator sini over denominator sin space straight r end fraction space equals space fraction numerator sin space 60 degree over denominator sin space 40 degree end fraction space equals space 1.347 end style
Whereas, the ratio of the same in option (1) is 1.535. So the correct answer is option (1)

Answered by Yashvanti Jain | 11th Dec, 2017, 07:07: PM