Correct Answer - Option 3 : 200 kms

**Given**

A person speed 40 km per hr. reached office 40 minutes late

A person speed 50 km per hr. reached office 20 minutes early

Let the distance between his office and park be x km.

Time is taken to reach office at 40 km per hr = x/40 hrs.

Time is taken to reach the park at 50 km per hr = x/50 hrs.

With the speed of 40 km per hr. he is 40 minutes late and at that of 50 km per hr. is 20 minutes early, so we can write.

**Calculation**

= (x/40 − 40/60) = (x/50 + 20/60)

⇒ (x/40 − x/50) = (20/60 + 40/60)

⇒ (5x-4x)/200 = 60/60

⇒ x/200 = 1

**∴ x = 200 kms**