Number 3 is 5
And 4 is 100.8
Answer:
Erik's average speed exceeds the speed limit by 6.91 miles per hour.
Step-by-step explanation:
Let suppose that Erik travels at constant speed. Hence, the speed (
), measured in miles per hour, is determined by following equation of motion:
(1)
Where:
- Distance, measured in miles.
- Time, measured in hours.
Please notice that a hour equals 60 minutes. If we know that
and
, then the speed of Erik is:


Which is 6.91 miles per hour above the speed limit.
60t +60 = 80t
subtract 60t from both sides of=
20t = 60
t = 3
The two trains are the same distance from Chicago at 3pm, at that time both trains will have covered 240 miles