Question 1057601: I'm having trouble answering the bottom two questions!! Please help as soon as possible and also please SHOW ALL WORK !!! Thank you !!
You and your friend are driving 379 miles from Los Angeles to San Francisco. Your friend leaves first, driving 52 miles per hour. She is 32 miles from Los Angeles when you leave, driving 60 miles per hour. How far do each of you drive before you are side by side? Write an equation to represent the situation and solve.
*If you left Los Angeles at 6 am when will you get to San Francisco?
*At what time would your friend reach San Francisco?
Answer by Boreal(15235)   (Show Source):
You can put this solution on YOUR website! x are the number of hours from time you leave.
At 52 mph, it takes your friend 32/52 of an hour to drive 52 miles.
Your speed is 60 mph
You have to make up 32 miles, and you are 8 mph faster than your friend. It will take you 4 hours, 32/8.
Alternatively, you are gone 60x miles, where x is the number of hours you've driven. Your friend has gone 52x+32 miles
See them equal
60x=52x+32, units hours
8x=32
x=4 hours
You will have driven 4 hours at 60 mph and gone 240 miles
Your friend will have driven 4 hours at 52 mph and gone 208 miles PLUS the 32 mile head start, for 240 miles.
It will take you 379/60 or 6.31667 hours to get to SF.
.31667*60=19 minutes
You will arrive in SF at 12:19 pm
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At 6 am, your friend has already gone 32 miles and has 347 miles to go.
At 52 mph this will take 6.6730 hours, or 6h40.38m. Multiply the 0.6730 by 60 to convert decimal hours to minutes.
Your friend will arrive at 12:40.38 pm, and .38 m is .38*60 or 22.8 sec. 12:40.22.8 pm
You can check that by taking 32/52, the fraction of an hour driven before 6 am, which is 0.615 hr or 36.92 m
Your friend needs 7.288 hr to go to SF (7h17.30m) and left at 6:00-36.92 m or at 5h23.08 m.
Adding the 7h 17.28 min to that is 12:40.38 m
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