Question 798926
First lets see how far the second car will go in 6 hours while driving 65mph.
{{{(65miles/cross(hour))* 6cross(hours) = 390miles}}}
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Now lets see how far the first car will go in 6 hours while driving 55mph.
{{{(55miles/cross(hour))* 6cross(hours) = 330miles}}}
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Subtract the mileage of the two cars.
{{{390miles - 330miles = 60miles}}}
The slower car would need a 60 mile head start.
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To calculated that time-wise, divide 60miles by 55miles/hour.
{{{(60cross(miles)/(55cross(miles)/hour)) = 1.091hours}}}
You can also turn the decimal places of the hour to minutes by multplying them by 60.
0.091 * 60 = 5.46
So the slower car would need about a one hour and 6 minute head start.