Arun and Bhadra are brothers. In how many years from now will Bhadra’s age be 50 years ? •
I. The ratio of the current ages of Arun and Bhadra is 5 : 7 respectively.
II. Bhadra was born 10 years before Arun.
III. 5 years hence, Arun’s age would be three-fourth of Bhadra’s age at that time.

I & II : Let Arun's age = $$x$$ years

=> Bhadra's age = $$x + 10$$ years

$$\therefore \frac{x}{x + 10} = \frac{5}{7}$$

=> $$7x = 5x + 50$$

=> $$7x - 5x = 2x = 50$$

=> $$x = \frac{50}{2} = 25$$

=> Bhadra's age = $$25 + 10 = 35$$ years

Thus, I & II are sufficient.

II & III : Let Arun's age = $$x$$ years

=> Bhadra's age = $$x + 10$$ years

$$\therefore \frac{x + 5}{x + 15} = \frac{3}{4}$$

=> $$4x + 20 = 3x + 45$$

=> $$4x - 3x = 45 - 20$$

=> $$x = 25$$

=> Bhadra's age = $$25 + 10 = 35$$ years

Thus, II & III are sufficient.

I & III :  Let Arun's age = $$5x$$ years

=> Bhadra's age = $$7x$$ years

$$\therefore \frac{5x + 5}{7x + 5} = \frac{3}{4}$$

=> $$20x + 20 = 21x + 15$$

=> $$21x - 20x = 20 - 15$$

=> $$x = 5$$

=> Bhadra's age = $$7 \times 5 = 35$$ years

Thus, I & III are sufficient.

$$\therefore$$ Any two of the three statements are sufficient.