Correct Answer - Option 3 : 3 hour

**Given****∶**

Speed of Alpha = 60 kmph

Speed of Beta = 80 kmph

**Formula Used****∶**

Time = Distance / Speed

**Calculation****∶**

Distance covered by Alpha in 1 hour = 60 km

Beta starts after 1 hour, he is driving with the speed of 80 kmph

Relative speed of Alpha and Beta = 80 kmph – 60 kmph = 20 kmph

Hence, they will meet in = Distance covered by Alpha / Relative speed = 60 / 20 = 3 hr.

**∴ Alpha and Beta will meet after 3 hours.**