Speed P6

Tony and Charles took part in a car race. Tony drove at a speed of 90km/h. Both of them did not change their speed throughout the race. When Charles had covered 1/3 the distance, Tony was 15 km in front of him. Tony reached the finishing line at 9.35 a.m. At what time did Charles reach the finishing line?


T [     ][15]
C [     ]

                        9.35 am         time?
                          |                    |
T [     ][     ][     ][15][15][15]
C [     ][     ][     ]
                          |
                         time? =   time?

15 x 3 = 45 km

45 / 90 = 1/2 h
            = 1/2 x 60 min
            = 30 min

             25 min        5 min
     |----------------|-----------|
9.35 am           10 am       10.05 am

It was 10.05 a.m.