SOLUTION: On a 255 mile trip gary traveled at an average of 70 mph, got a speeding ticket, and then traveled at 60 mph for the remainder of the trip. If the entire trip took 4.5 hours and

Algebra ->  Rate-of-work-word-problems -> SOLUTION: On a 255 mile trip gary traveled at an average of 70 mph, got a speeding ticket, and then traveled at 60 mph for the remainder of the trip. If the entire trip took 4.5 hours and       Log On


   

Question 178509: On a 255 mile trip gary traveled at an average of 70 mph, got a speeding ticket, and
then traveled at 60 mph for the remainder of the trip. If the entire trip took 4.5 hours and the speeding ticket stop took 30 minutes, how long did gary speed before he got stopped?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
On a 255 mile trip Gary traveled at an average of 70 mph, got a speeding ticket,
and then traveled at 60 mph for the remainder of the trip. If the entire trip
took 4.5 hours and the speeding ticket stop took 30 minutes, how long did Gary
speed before he got stopped?
:
Let t = time driven at 70 mph
The total driving time was 4 hrs, therefore:
(4-t) = time at 60 mph
:
Write a distance equation; dist = speed * time
;
Dist at 70 + dist at 60 = 255
:
70t + 60(4-t) = 255
:
70t + 240 - 60t = 255
:
70t - 60t = 255 - 240
:
10t = 15
t = 15%2F10
t = 1.5 hrs at 70 mph
:
:
check solution (time at 60 mph: 4 - 1.5 = 2.5hrs)
1.5(70) + 2.5(60) =
105 + 150 = 255 mi confirms our solution