Present ratio of the ages of Babita and Sunita is 7:9, 5 years ago, this ratio was 1:2. Find the present age of Babita.

Correct option is C

Given:
The present ratio of the ages of Babita and Sunita = 7 : 9
5 years ago, this ratio of the ages of Babita and Sunita = 1: 2
Solution:
Let the present age of Babita and Sunita be 7x and 9x respectively
Five years ago,
Babita's age = (7x - 5)
Sunita's age = (9x - 5)
According to given 
​$$\frac{7x - 5}{9x - 5} = \frac{1}{2}\\\Rightarrow (7x - 5) \times 2 = (9x - 5)\\\\\Rightarrow 14x - 10 = 9x - 5\\\Rightarrow 14x - 9x = -5 + 10\\\Rightarrow 5x = 5\\\Rightarrow x = 1\\$$​​
∴ Present age of Babita is 7x = 7 years.