Correct Answer - Option 1 : 120 km/h

Given:

A woman goes from place S to place T at the speed of 150 km/hr and return at the speed of 100 km/hr.

Concepts used:

Average speed = (2S1 × S2)/(S1 + S2)

S1 → Speed at which a woman travelled from place S to T

S2 → Speed at which a woman returned from place T to S.

Calculation:

Average speed = (2S1 × S2)/(S1 + S2)

⇒ 2 × 150 × 100/(150 + 100)

⇒ 30000/250

⇒ 120 km/h

∴ Average speed in whole journey is 120 km/hr.