Question 998586: A man could arrive on time for an appointment if he drove his car at 40 mph; however, since he left the house 15 minutes late, he drove the car at 50 mph and arrived 3 minutes early for the appointment. How far from his house was his appointment?
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! A man could arrive on time for an appointment if he drove his car at 40 mph; however,
since he left the house 15 minutes late, he drove the car at 50 mph and arrived 3 minutes early for the appointment.
How far from his house was his appointment?
:
Since we are dealing in mph, change the minutes to hr
15 min: 15/60 = .25 hrs
3 min: 3/60 = .05 hrs
:
Let t = his normal drive time to work in hrs
then
40t = the distance to work
Write a distance equation; dist = speed * time
50(t-.25 + .05) = 40t
50(t - .20) = 40t
50t - 10 = 40t
50t - 40t = 10
10t = 10
t = 1 hr normal time to work
therefore
40(1) = 40 mi to work
:
:
Confirm this by finding the dist when he went 50 mph for 48 min (.8hrs)
50(1-.25+.05) = 50(.8) = 40 mi also
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