1.  If the incomes of two Companies were equal in 1999, then what was the ratio of expenditure of Company X to that of Company Y in 1999 ?
A. 6 : 5
B. 5 : 6
C. 11 : 6
D. 16 : 15
E. 15 : 16

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 = x - E1 x 100     =>     50 = x - 1    
E1 100 E1


 => x = 150E1 /100 .... (i)

Also, for Company Y we have:

60 = x - E2 x 100     =>     60 = x - 1      
E2 100 E2

=> x = 160E2 / 100 ... (ii)

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

150 E1 = 160 E2     =>     E1 = 160 = 16
100 100 E2 150 15

(Required ratio).