A boy rides his bicycle 10 km at an average speed of 12 km/hr. and again travels 12km at an average speed of 10km/hr. His average speed of for the entire trip is approximately

• ক 10.8 km/hr ✅ সঠিক উত্তর
• খ 20 km/hr
• গ 15 km/hr
• ঘ 12.4 km/hr