Question 773257
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Michael drove to a friends house at a rate of 40 mph. He returned by the same route at a rate of 45 mph. The driving time for the round trip was 4 hours. What is the distance Michael Traveled?
Ans:
Let the distance to the friends house be x miles
Distance = Speed * time, or time = Distance / speed.
So time taken for driving to the friend's house = x/40
And time taken for return = x/45
Total time = x/40 + x/45
Total time is given to be 4 hours. So we get the equation
{{{x/40 + x/45 = 4}}} Multipyling by 360 which is the LCM of 40 and 45,
{{{9x + 8x = 1440}}}
{{{17x = 1440}}}
{{{x = 1440/17 = highlight(84.71)}}} miles approximately.
:)
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