Level 3
City X and City Y are 420 km apart. At 3.45 p.m., Joni is travelling at a uniform speed left City X for City Y while Ben set off from City Y to City X along the same road at a uniform speed, which was 12 km/h slower than that of Joni. The two met at 6.45 p.m.
  1. Find the speed of Joni.
  2. If Ben continued to travel at the same speed, how long would it take for him to reach his destination after the two met? Express the answer in mixed number.
5 m