Cross road

From the junction of two streets that are perpendicular to each other, two cyclists (each on another street) walked out. One ran 18 km/h and the second 24 km/h. How are they away from

a) 6 minutes,
b) 15 minutes?

Correct answer:

a =  3 km
b =  7.5 km

Step-by-step explanation:

$$\begin{gathered} v_1=18\text{ km/h } \\ {v}_2=24\text{ km/h } \\ v=\sqrt{v_1^2+v_2^2}=\sqrt{18^2+24^2}=30\text{ km/h } \\ {t}_1=6\text{ min}\to \text{ h}=6\mathrm{/}60\text{ h}=0.1\text{ h } \\ a=t_1\cdot v=0.1\cdot 30=3\text{ km} \end{gathered}$$

$$\begin{gathered} t_2=15\text{ min}\to \text{ h}=15\mathrm{/}60\text{ h}=0.25\text{ h } \\ b=t_2\cdot v=0.25\cdot 30={\displaystyle \frac{15}{2}}={\displaystyle \frac{15}{2}}\text{ km}=7.5\text{ km} \end{gathered}$$

Try another example

Related math problems and questions:

• Two cyclists
  Two cyclists started from crossing in the same time. One goes to the north speed 20 km/h, the second eastward at speed 26 km/h. What will be the direct distance cycling 30 minutes from the start?
• Movement
  From the crossing of two perpendicular roads started two cyclists (each at the different road). One runs at average speed 28 km/h, the second at average speed 24 km/h. Determine the distance between them after 45 minutes cycling.
• Young Cyclists
  Charlie and Peter will attend the Young Cyclists Meeting today. Peter is still not able to start, so Charlie went first alone. Peter followed him in 20 minutes. How long does he take to reach Charlie? Charlie is traveling at an average speed of 15km/h, Pe
• Speed of Slovakian trains
  Rudolf decided to take the train from the station 'Ostratice' to 'Horné Ozorovce'. In the train timetables found train Os 5409 : km 0 Chynorany 15:17 5 Ostratice 15:23 15:23 8 Rybany 15:27 15:27 10 Dolné Naštice 15:31 15:31 14 Bánovce nad Bebravou 15:35 1
• Two aircraft
  Two planes fly to the airport. At some point, the first airplane is away from the airport 98 km and the second 138 km. The first aircraft flies at an average speed of 420 km/h, the second average speed is 360 km/h, while the tracks of both planes are perp
• Car and cyclist
  Cyclist started from town at a speed of 18 km/h. After 1 hour 30 min started the car from town and caught up with the cyclist in 50 minutes. How fast was a car?
• Runner
  Peter ran a speed of 12.4 km / h. After 45 minutes running he had a hiatus. The track is 31 km long. How many kilometers he still to run if he still running at the same speed?
• Scouts
  The boys from scout group traveled 5 days distance 115 km. Every day walked 1.5 km less than the previous day. How many kilometers scouts walked in the first day?
• Grandmother
  Mom walked out to visit her grandmother in a neighboring village 5km away and moved at a speed of 4km/h. An hour later, father drove down the same road at an average speed of 64km/h. 1) How long will take to catch mom die? 2) What is the approximate dista
• Failure
  Drivers of passenger cars have calculated that at a speed of 60 km/h arrives at destination within 40 minutes. After 20 km refrain five minutes due a technical failure. How fast must go the rest of the way to the finish came at the scheduled time?
• Average speed
  The average speed of a pedestrian who walked 10 km was 5km/h, the average speed of a cyclist on the same track was 20km/h. In how many minutes did the route take more than a cyclist? Q
• Klara
  Klara and Jitka went on a hiking trip at 13 o'clock at speed 5km/h. At 14 o'clock, Tomas ride on the bike at an average speed of 28 km/h. How many hours and at what distance from the beginning of the road Tomáš caught the two girls?
• Athletic oval
  On the 400 m athletic oval, two athletes started back to back from the same level. After the starting shot, they both ran away from each other at the same time. Athlete A ran at 15 km/h, and Athlete B ran at 17 km/h. A) in how many seconds did the athlete
• Two ships
  The distance from A to B is 300km. At 7 am started from A to B a ferry with speed higher by 20 km/h than a ship that leaves at 8 o'clock from B to A. Both met at 10h 24min. Determine how far they will meet from A and when they reach the destination.
• Overtaking
  On the direct road, the passenger car overtakes the slower bus by starting to overtake 20 meters from the bus and after passing it ahead of it again 20 meters away. The car overtakes at a steady speed of 72 km/h, the bus goes at a steady speed of 54 km/h.
• Scale of map
  James travels one kilometer in 12 minutes. The route walked for half an hour measured on the map 5 cm. Calculate how many kilometers James walked for half an hour. Find the scale of the map.
• Trains for people
  It is said that the train is synonymous to delay. Calculate the average speed of travel by train long 85 km, with regular train leave at 7:00 and arrive at 8:18, but train is late and has departure at 8:10 and arrive at 9:27.