A car moves with a speed of 30km/hr for half an hr,25km/hr for 1he and 40km/hr for 2hrs. What is the average speed of car?
speed=30km/h
time=0.5hrs
distance=s*t
=15km
speed=25km/h
time=1hrs
distance=s*t
=25km
speed=40km/h
time=2hrs
distance=s*t
=80km
average speed= total distance/total
time taken
= (15+25+80)/(1+2+0.5)
= 120/3.5
= 34.28km/h.
the question is not what i ask
To find the average speed of the car, you need to calculate the total distance traveled by the car and divide it by the total time taken.
First, let's calculate the distance traveled at each speed:
Distance1 = Speed1 x Time1
= 30 km/hr x 0.5 hr
= 15 km
Distance2 = Speed2 x Time2
= 25 km/hr x 1 hr
= 25 km
Distance3 = Speed3 x Time3
= 40 km/hr x 2 hr
= 80 km
Next, add up the distances traveled to get the total distance:
Total Distance = Distance1 + Distance2 + Distance3
= 15 km + 25 km + 80 km
= 120 km
Now, let's calculate the total time taken:
Total Time = Time1 + Time2 + Time3
= 0.5 hr + 1 hr + 2 hr
= 3.5 hr
Finally, divide the total distance by the total time to find the average speed:
Average Speed = Total Distance / Total Time
= 120 km / 3.5 hr
≈ 34.286 km/hr
Therefore, the average speed of the car is approximately 34.286 km/hr.
average speed = total distance travelled / total time
Total distance travelled
= 30km/h * 0.5 h + 25km/h * 1 2/3 h
+ 40km/h *2 h
= 136.667 km
Total time = 0.5+1 2/3 + 2
= 4.1667 h
Average speed = 136.667/4.1667
= 32.8 km/h