Answer : Option D

Explanation :

Let the incomes of each of the two Companies X and Y in 1999 be Rs. x.

And let the expenditures of Companies X and Y in 1999 be E₁ and E₂ respectively.

Then, for Company X we have

 50 = \(\frac { X - E1} { E1 } \) x 100    \(\frac { 50 } {100}\)= \(\frac { X } { E1 } \) -1      x = \( \frac { 150 } { 100 } \)  E1 ... (i)

Also, for Company Y we have:

 60 = \(\frac { X - E2} { E2 } \) x 100   \(\frac { 60 } {100}\)  = \(\frac { X } { E2 } \) -1       X = \( \frac { 160 } { 100 } \) E2.. (ii)

From (i) and (ii), we get:

\( \frac { 150 } { 100 } \) E1 = \( \frac { 160 } { 100 } \) E2   \( \frac { E1} { E2 }\) = \( \frac { 160 } { 150 } \) = \(\frac { 16 } {15 }\) (Required ratio)