Bank Math Master১টি পরীক্ষায় এসেছেপ্রশ্ন ২A man covers half of his journey at 10 km/h and the remaining half at 4 km/h. His average speed is:ক6.5 km/hখ7.5 km/hগ5.71 km/hঘ6.82 km/hউত্তর দেখুন