Given that the lengths of the paths of a balls thrown with different speeds of two boys are the same, if they take 6 seconds and 10 seconds respectively to cover the same length, what is the average speed of travel for the first throw, if the speed for the second is 102 km/h?

170

             I^st        :         II^nd

Time       6         :         10

               3         :          5

Speed     5         :          3

              ↓                     ↓

            ×34                 ×34

              ↓                     ↓

            170                102