Speed P6 2011 PSLE

Alex and Bob were running round a 400 m circular track. Alex ran at a speed of 190 m/min while Bob ran at a speed 25 m/min slower than Alex. When Alex ran 300 m more than Bob, how many complete rounds had he run?


25 m  -->  1 min


                  300
300 m  -->  -----  x  1  =  12 min
                    25


190  x  12  =  2280 m


2280  ÷ 400 =  5.7
                    ≈  5 complete rounds


It was  5 complete rounds.