Correct option is B
Given:
Difference between ages of two persons = 30years
3 years ago elder one was 3 times the younger
Solution:
Let the age of younger person be x
Then age of elder one is x+30
Age of younger 5 years ago = x-5
Age of elder person 5 years ago = x+30-5 = x+25
According to question:
x + 25 = 3(x-5)
x + 25 = 3x -15
x = 20
The younger person is 20 years old