SOLUTION: Sam is late for his class. If he drives the speed limit, he'll get to class in 24 minutes. Instead, if sam drives 10 mph faster the the speed limit, he could get to class in 20 min

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Question 561320: Sam is late for his class. If he drives the speed limit, he'll get to class in 24 minutes. Instead, if sam drives 10 mph faster the the speed limit, he could get to class in 20 min. How far did sam drive to his class? How fast was sam going?
Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
Sam is late for his class.
If he drives the speed limit, he'll get to class in 24 minutes.
Instead, if sam drives 10 mph faster the the speed limit, he could get to class in 20 min.
How far did sam drive to his class? How fast was sam going?
:
Let s = speed limit
then
(s+10) = his speed over the speed limit
:
Change 24 min to hrs: 24/60 = 2/5 hr
Change 20 min to hrs: 20.60 = 1/3 hr
:
Write a distance equation: dist = speed * time
:
(s+10) = s
multiply both sides by 15, results
5(s+10) = 3(2s)
5s + 50 = 6s
50 = 6s - 5s
s = 50 mph is the speed limit and 60 mph is over the speed limit
:
Find the distance: *50 = 20 mi
Check the distance: *60 = 20 mi