Question 1121058
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Find the average speed on the level road IF the entire trip was 490 miles
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<pre>
                SPEED           TIME       DISTANCE
Level            r              6          6r
Winding         r-20            4          4(r-20)
TOTAL                                      490
</pre>


{{{highlight_green(6r+4(r-20)=490)}}}
Solve for r.