2) the set of irrational numbers
3) the set of non-negative integers
4) the set of real numbers
Remark
Average Speed = Total distance divided by total time.
Total Time
2 hours + 3 hours = 5 hours. The total time is 5 hours.
Total Distance
d = rate * time
d1 = 40 km/hour * 2 hours = 80 km
d2 = 50 km/hour * 3 hours = 150 km
d = d1 + d2
d = 80 + 150 = 230 km
Average Speed
Av = Total distance / Total Time = 230 / 5 = 46 km/hr