Fog

The car started in fog at speed 30 km/h. After a 12-minute drive, the fog dissipated and the driver drove next 12 minutes distance 17 km. On the last 17 km long again the driving conditions deteriorated and the driver drove the speed of 51 km/h.

a) Calculate the distance of the first section, the speed on the second section and the time on third section.
b) Construct the graph distance vs. time t.
c) Calculate the average speed for the first two sections and the average speed on the last two sections. When can the average rate calculated as the arithmetic mean of the individual speeds? Judge answer.

Correct result:

s1 =  6 km
v2 =  85 km/h
t3 =  0.3333 h
c1 =  57.5 km/h
c2 =  63.754 km/h

Solution:

s1=30 12/60=6 km
v2=17/(12/60)=85 km/h
t3=17/51=0.3333 h
c1=(s1+17)/((12+12)/60)=1152 km/h=57.5 km/h
c2=(17+17)/(12/60+t3)=63.754 km/h



We would be pleased if you find an error in the word problem, spelling mistakes, or inaccuracies and send it to us. Thank you!






Showing 0 comments:
avatar




Tips to related online calculators
Looking for help with calculating arithmetic mean?
Looking for a statistical calculator?
Do you want to convert velocity (speed) units?
Do you want to convert time units like minutes to seconds?

 
We encourage you to watch this tutorial video on this math problem: video1

Next similar math problems:

  • Constant motion
    car_36 The car has undergone constant motion 120 km in 1 hour 30 minutes. Determine its average speed. Determine how long car drove in the first 20 minutes and 50 minutes from the start of the move.
  • Athletic competition
    runners_7 In a 400 meter athletic competition, a participant covers the distance as given below. find the average speed? first 80 meters 10 m/s next 240 meters 7.5 m/s last 80 meters 10 m/s
  • Two trains
    two-trains Two trains go at each other. First at speed 40 km/h and the second at speed 60 km/h. At what distance will be 30 minutes before they will meet?
  • Driver
    truck_2 The driver of the supply car reckoned that at the average speed of 72 km/h arrives to the warehouse for 1 1/4 hours. After 30 km however unintentionally drove to the gas station and have ten minutes delay. At what average speed would have to go the rest o
  • Express train
    trains_13 International express train drove from Kosice to Teplice. In the first 279 km, the track was repaired, and therefore it was moving at a speed of 10km/h less than it was scheduled to drive. The rest of the 465 km trip has increased the speed by 8 km/h than
  • Cars 2
    car_2 Opava is 360 km distance from Prešov. At 8:00 hour two cars started against each other from this cities at average speeds 88 km/h and 121 km/h. At what hour its will meet and what distance its travel if car started from Prešov is faster?
  • Motion 2
    motion2 At 10 o'clock started from place A car speed at 90 km/h. 20 minutes after started from the place B at speed 60 km/h another car. Distance places A and B is 120 kilometers. What time and where they meet?
  • Average
    old_automobile What is the average speed of the car, where half of the distance covered passed at speed 66 km/h and the other half at 86 km/h.
  • Znojmo
    car_3 From Znojmo to Brno started truck with a trailer at an average speed 53 km per hour. Against him 14 minutes later from Brno started car with an average speed of 1.2-times greater than the truck. How long and how far from Znojmo, they meet if the distance
  • Cycling trip
    bus_7 At 8 am started a group of children from the camp to day cycling trip. After 9:00 weather deteriorated sharply and the leader decided to send for the children bus on the same route, which started at 10 hours. For how long and at what distance from the cam
  • Two cars 2
    2cars Two cars started from two positions 87 km distant at the same time in opposite directions at speeds 81 km/h and 75 km/h. What was the distance between them after 2 hours 50 minutes of driving.
  • A car
    car_31 A car weighing 1.05 tonnes driving at the maximum allowed speed in the village (50 km/h) hit a solid concrete bulkhead. Calculate height it would have to fall on the concrete surface to make the impact intensity the same as in the first case!
  • Two cities
    cars_30 The car goes from city A to city B at an average speed of 70 km/h, back at an average speed of 50 km/h. If it goes to B and back at an average speed of 60 km/h, the whole ride would take 8 minutes less. What is the distance between cities A and B?
  • Tourists
    hiking From the cottage started first group of tourists at 10:00 AM at speed 4 km/h. The second started after them 47 minutes later at speed 6 km/h. How long and how many kilometers from the cottage will catch the first group?
  • Two cities
    cyclist_37 The distance between cities A and B is 132 km. At 9.00 am, the cyclist started the bike at an average speed of 24 km/h, and at 10.00 h started from the B cyclist at an average speed of 30 km/h. How long and far from A will they both meet?
  • Motorcyclist
    motorbike_3 From Trutnov, the motorcyclist started at an average speed of 60km/hour. At 12.30hrs the passenger car was started at a speed of 80km/hour. How many hours and at what distance from Trutnov will car catch a motorcycle?
  • Two cars
    cars_racing Two cars started against each other at the same time to journey long 346 km. The first car went 53 km/h and the second 53 km/h. What distance will be between these cars 20 minutes before meet?