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[ Cyanide ]
10-13-2008, 02:17 PM
I'm in tears trying to figure this out!

1) Carlos and Maria drove a total of 240 miles in 4.6 hours. Carlos drove the first part and averaged at 54mph. Maria drove the remainder of the trip, and averaged 51mph. For approximately how many hours did Maria drive? Round your answer to the nearest tenth.

2)
w+12
------- = 3/5 (three-fifths)
4w+7

stapel
10-13-2008, 02:30 PM
]1) Carlos and Maria drove a total of 240 miles in 4.6 hours. Carlos drove the first part and averaged at 54mph. Maria drove the remainder of the trip, and averaged 51mph. For approximately how many hours did Maria drive? Round your answer to the nearest tenth.
Carlos drove some distance "d". What expression could stand for how far Maria drove?

Carlos drove this distance at 54 miles per hour. Using "d = rt", what expression would then stand for his time? Using similar reasoning, what expression would stand for Maria's time?

What was the total time? What equation can you create with the total time and the expressions for the partial times?

]2)
w+12
------- = 3/5 (three-fifths)
4w+7
You multiplied through to clear the denominators and get a simple linear equation, and... then what?

Please be complete. Thank you! :D

Eliz.

Subhotosh Khan
10-13-2008, 02:49 PM
]I'm in tears trying to figure this out!

1) Carlos and Maria drove a total of 240 miles in 4.6 hours. Carlos drove the first part and averaged at 54mph. Maria drove the remainder of the trip, and averaged 51mph. For approximately how many hours did Maria drive? Round your answer to the nearest tenth.

This problem looks very much like the problem posted at:

viewtopic.php?f=8&p=118574 (http://www.freemathhelp.com/forum/viewtopic.php?f=8&p=118574)

2)
w+12
------- = 3/5 (three-fifths)
4w+7