Correct Answer - Option 2 : 520 km

**Given:**

A man travelled 3/5^{th} of the total distance by car

A men travelled 7/20^{th} of the total distance by bike

**Concept:**

Speed = Distance/Time

**Calculation:**

Let us assume total distance is X

⇒ 3X/5 + 7X/20 + 26 = X

⇒ 12X + 7X + 520 = 20X

⇒ X = 520 km

**∴ The required result will be 520 km.**