<PRE><B>Question 9449</B>
Let m be number of cars owned by Mark

    d be number owned by David

 m = 7 sqrt d

m + d = (sqrt 9)(27150/181)


   The right side is computed to be 450

 Then  7 sqrt d + d = 450

   (sqrt d)^2 + 7 sqrt d - 450 = 0

by quadratic formula 

sqrt d = [-7 + sqrt(49 +4(450))]/2

 We use the positve square root in answer  else m would be a negative number
Simplifying gives 

 sqrt d = 18

 d = 324

 m = 7 sqrt d

   = 126

 I used a calculator to get these intermediate answers 

 David has 324 cars and Mark has 126
 David has more cars.
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