Let present age of Arun is = 3X

and present age of Bhargava = 4X

Then 10 year ago Arun was half of Bhargava in age

(3X - 10) =(1/2)(4X-10)

(3X - 10) =( 2X-5)

X = 5

So present age of Arun is = 3X = 3*5 = 15

and Bhargava is = 4X = 4*5 = 20

Sum of their age = 15+20 = 35

**ANSWER = 35**