jane and sali cucled along the same 63 km route. jane took 3.5 hours to cycle the 63km. sali started to cycle 4 minutes after jane started to cycle. sali caught up with jane when they both cycled 30km jane and sali both cycled at constant speeds. work out the speed in m/s

we know that

speed=distance/time
Jane speed is ------> 63 km/3.5 hours------> 18 Km/hours

1 Km is equals to-------------> 1000 m
1 hour is equals to---------> 3600 sec
so
18 Km/hour------> 18*1000/3600------> 5 m/sec

for distance =30 Km
 Jane s time=?
time=distance/speed------> time=30000/5----> time=6000 sec----> 100 min

the time it took Sali to reach 30 km was-----> 100 min-4 min---> 96 min
Sali speed is---> 30000/96 min--> 312.5 m/min----> 312.5/60---> 5.21 m/sec

the answer is
Jane speed is 5 m/sec
Sali speed is 5.21 m/sec