Question 1110941
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Let r be the rate of moving at the slower highway, in mph

Then the rate on the faster highway is (r+8) mph.


The total distance traveled equation is

5*(r+8) + 3r = 456   miles.

5r + 40 + 3r = 456

8r = 456 - 40 = 416

r = {{{416/8}}} = 52.


<U>Answer</U>.  52 mph at the slower highway and 52+8 = 60 mph at the faster highway.
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