Question 938138
You drive 100 miles. Over the first 50 miles you drive 50 mph, and over the second 50 miles you drive V mph. 
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 Calculuate the time spent on the first 50 miles and on the second 50 miles. 
t = {{{50mi/(50mph) = 1hr}}}, t = {{{50mi/Vmph}}}
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 Calculate the average speed for the entire 100 mile journey.
{{{100mi/(1 + 50/V)}}}
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 If you want to average 75 mph for the entire journey, what is V?
{{{100mi/(1 + 50/V) = 75mph}}} 
75(1 + 50/V = 100
1 + 50/V = 1 1/3
{{{50/V = 1/3}}}
150mph = V
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