document.write( "Question 1085787: Assume that the stopping distance of a van varies directly with the square of the speed. A van traveling 20 miles per hour can stop in 30 feet. If the van is traveling 28 miles per hour, what is its stopping distance?\r
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\n" ); document.write( "\n" ); document.write( "If the van is traveling 28 miles per hour, the stopping distance \n" ); document.write( "

Algebra.Com's Answer #699878 by htmentor(1343) $\"\"$ $\"About$

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Since the distance varies as the square of the speed, we can express this relationship as:
\n" ); document.write( "d = k*s^2 where k = a constant
\n" ); document.write( "For two sets of distances and speeds (d1,s1) and (d2,s2) we can write
\n" ); document.write( "d1 = k*s1^2 and
\n" ); document.write( "d2 = k*s2^2
\n" ); document.write( "Thus d1/s1^2 = d2/s2^2 -> d2 = d1*(s2/s1)^2
\n" ); document.write( "Putting in the values, we have
\n" ); document.write( "d2 = 30*(28/20)^2 = 58.8 ft \n" ); document.write( "

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