a,b,c,d,e and f are positive numbers such that bcdef/a=4, acdef/b=9, abdef/c=16,abcef/d=1/4, abcdf/e=1/9,abcde/f=1/16. Then (a+c+e)-(b+d+f)=_______
a + c + e - (b + d + f) = 23.
wait why
+28 
