Question 458690
David got in his '29 Ford and started driving west from Florida at a constant speed of 30 miles per hour. An hour later Anna got in her '31 Buick and started driving west from Florida at a constant speed. After driving 4 hours Anna had passed David and was 10 miles ahead of him. How fast was Anna driving? 
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David DATA:
rate = 30 mph ; time = 5 hrs ; distance = rt = 30*5 = 150 miles 
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Anna DATA:
distance = 160 miles ;  time = 4 hrs ; rate = d/t = 160/4 = 40 mph
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Anna's rate = 40 mph
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Cheers,
Stan H.
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