M mathsisharddd New Member Joined Aug 9, 2008 Messages 3 Gender Female HSC 2008 Aug 14, 2008 #1 I'm doing a CSSA trial and just came up against this question... I did i) no worries, it's just x/16 = 12.5/5 then 12.5x16.5 = 40. but ii) the answer is coming out as 62.8cm^2... how is it this? isn't it pi x 16 x 5 = 231.3cm^2?
I'm doing a CSSA trial and just came up against this question... I did i) no worries, it's just x/16 = 12.5/5 then 12.5x16.5 = 40. but ii) the answer is coming out as 62.8cm^2... how is it this? isn't it pi x 16 x 5 = 231.3cm^2?
PC Member Joined Aug 19, 2004 Messages 639 Location Sydney Gender Undisclosed HSC N/A Aug 14, 2008 #2 Remember that the area of an ellipse is πab, where a and b are the "radii". So Area of smaller ellipse = πab = π x 8 x 2.5 = 62.8 cm2
Remember that the area of an ellipse is πab, where a and b are the "radii". So Area of smaller ellipse = πab = π x 8 x 2.5 = 62.8 cm2