The cyclist

The cyclist drove from A to B, 60 km away. The first half drove at 30km/h, the second at 20km/h. How long did it take for him?

Correct answer:

t =  2.5 h

Step-by-step explanation:

$$\begin{gathered} s=60\text{ km } \\ {v}_1=30\text{ km/h } \\ {v}_2=20\text{ km/h } \\ {s}_1=s\mathrm{/}2=60\mathrm{/}2=30\text{ km } \\ {t}_1=s_1\mathrm{/}{v}_1=30\mathrm{/}30=1\text{ h } \\ {t}_2=s_1\mathrm{/}{v}_2=30\mathrm{/}20={\displaystyle \frac{3}{2}}=1.5\text{ h } \\ t=t_1+t_2=1+1.5={\displaystyle \frac{5}{2}}={\displaystyle \frac{5}{2}}\text{ h}=2.5\text{ h} \end{gathered}$$

Try another example

Related math problems and questions:

• Motion against
  From two places 36 km apart, a pedestrian and a cyclist will go straight opposite each other. How long will they meet if the speed of the pedestrian is 4 km/h and the cyclist 12 km/h?
• Constant motion
  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.
• Two vans
  At 8:30 a. M. , two vans leave at a parking area. They travel in opposite directions: one van travels at 48 km/h and the other at 62 km/h. At what time will the cars be 550 km apart?
• Cyclist and car
  A cyclist who runs at a speed of 20km per hour will arrive at the finish in 4.5 hours. How fast does the car have to drive the same route in 2 hours?
• Cyclist 12
  What is the average speed of a cycle traveling at 20 km in 60 minutes in km/h?
• Two cities
  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 am started from the B cyclist at an average speed of 30 km/h. How long and far from A will they both meet?
• The tourist
  The tourist came started from the hostel at an average speed of 5km/h. Half an hour later, the bicyclist started along the same route at a speed of 20km/h. How many minutes will a cyclist catch up and how many kilometers will he go?
• Cyclist
  A cyclist is moving at 35 km/h and follow pedestrian who is walking at speed 4 km/h. Walker has an advantage 19 km. How long take cyclist to catch up with him?
• Average speed
  The average speed of a good cyclist is 30 km/h. The average speed of the less able is 20 km/h. They both set off on the same route at the same time. Good cyclist drove it 2 hours earlier. How long was the route?
• 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?
• Car - road
  Car started at 11:40 at speed 54 km/h from A and to B arrived at 12:20. Determine the distance A and B.
• Cars motion
  From point A car start at the speed of 90 km/h. Against it departs from the point B at the same time another car at 60 km/h. For how long and where they met if the distance between A and B is 180 km?
• Against each other
  From two points A, B distant 23 km at the same time started two cars against each other at speeds 41 km/h and 65 km/h. How long does cars meet and what distance passes each of them?
• Motion 2
  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?
• Pedestrian and the cyclist
  Pedestrian and cyclist went against each from the two cities that are distant 40 km. Pedestrian started 30 minutes before the cyclist and walk an average speed of 5 km/h. What speed went cyclist when met after 120 minutes from the start of the pedestrian?
• Cyclist 9
  A cyclist travels at a speed of 4.25 km per hour. At that rate, how far can he travel in 3.75 hours?
• The cyclist
  The cyclist went from village to town. The first half of the journey went at 20 km/h. The second half of the journey, which mostly fell, went at 39 km/h. All journey took 88 minutes. Calculate the distance from the village to the town.