A drives for 2 hours, 2.5 hours, 3 hours, 2 hours and 2.5 hours in five days of a week, respectively. His speeds on these days are 45km/h, 50km/h, 60km/h, 70km/h and 80km/h, respectively. What is his average speed for the week?
- A68.02 km/h
- B60.8 km/h
- C61.25 km/h
- D64.08 km/h
Solution & Step-by-step Explanation
Average speed is calculated as the total distance divided by the total time.
Total Time=2+2.5+3+2+2.5=12hours
Now, find the distance traveled on each day (Distance=Speed×Time):
Day 1: 45×2=90km
Day 2: 50×2.5=125km
Day 3: 60×3=180km
Day 4: 70×2=140km
Day 5: 80×2.5=200km
Total Distance=90+125+180+140+200=735km
Average Speed=
Total Time
Total Distance
=
12
735
=61.25km/h
Total Time=2+2.5+3+2+2.5=12hours
Now, find the distance traveled on each day (Distance=Speed×Time):
Day 1: 45×2=90km
Day 2: 50×2.5=125km
Day 3: 60×3=180km
Day 4: 70×2=140km
Day 5: 80×2.5=200km
Total Distance=90+125+180+140+200=735km
Average Speed=
Total Time
Total Distance
=
12
735
=61.25km/h