<PRE><B>Question 820440</B>
s = d / t
t = d / s
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a = (100/2)/65
a = 50/65
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b = (100/2)/75
b = 50/75
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total time:
t = a + b
t = 50/65 + 50/75
t = 50(75)/(65)75 + 50(65)/(65)75
t = 1.4358974 hours
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average speed:
s = d / t
s = 100 / 1.4358974
s = 69.642857 mph
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note that:
(65 + 75)/2 = 70 mph is NOT the correct answer
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Solve systems of linear equations up to 6-equations 6-variables:
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