if a,b,c,and d are proportional then the mean proportion between a^2+c^2 and b^2+d^2 is ?

• ac/bd;
  proportion between a^2+c^2 and b^2+d^2 = a^2(1+c^2/a^2)/b^2(1+d^2/b^2) ;
  since,a/c=d/b;
  so a^2/b^2;
  answer is ac/bd
• 10 years agoHelpfull: Yes(1) No(7)
• Let the mean proportion be 'X' .
  Then, (a² + c²) / X = X / (b² + d²)
  ⇒ X² = (a² + c²) (b² + d²)
  ⇒ X² = a²b² + a²d² + c²b² + c²d²
  ⇒ X² = a²b² + ad.bc + ad.bc + c²d² [ since , ad = bc as per proportionality of a,b,c and d ]
  ⇒ X² = a²b² + 2 (abcd) + c²d²
  ⇒ X² = ( ab + cd )²
  ⇒ X = ( ab + cd ) is the ANSWER .
• 6 years agoHelpfull: Yes(1) No(0)