<PRE><B>Question 944335</B>
d=distance from town to park
{{{d/4 mph+d/20 mph=18 hrs}}}
You may want to stop here and try the rest on your own
To solve:multiply both sides by 4 mph
{{{(d*4mph)/4 mph+(d*4mph)/20 mph=18hrs(4mph)}}}
{{{d+(d/5)=72 mi}}} combine terms on left side
{{{(5d/5)+(d/5)=72 mi}}}
{{{(5d+d)/5=72 mi}}} Multiply each side by 5
{{{6d=360 mi}}} Divide each side by 6
{{{d=60 mi}}}
ANSWER The park is 60 miles from town
CHECK 
It took 15 hrs to get there at 4mph and 3 hrs to return at 20 mph=18 hrs round trip 
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