Answer:
11 km/hr.
Step-by-step explanation:
Given information:
Simulated speed = 20/km/h
Time = 15 mins = 1/4 hr = 0.25 hr
Distance Covered as per simulated speed = 
Position of Julian according to the app =
.
Actual distance covered by the bike is

Formula for speed:



Therefore, the average speed of Julian is 11 km/hr.
The answers are (-3, -4) and (-5, -4).
For the answer to the question above, we'll have to use the formula for velocity which is v =<u> d
</u> t and d = vt
Since the total distance is given, therefore we can get the time and it will look like this.
220t + 250t = 1880
<u>470t</u> = <u>1880
</u>470 470
the problem indicates that the train runs 250kph
Let's substitute:
d = 250(4)
the distance traveled by Lian is 1000km
<u>
</u>