Okay, I've posted after a long time, I know... But I'm here with another doubt.

The ratio between the sides of 2 regular polygons is 4 : 5 and the ratio between the interior angles is 15 : 16. Find the number of sides.

Thanks!

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- Jan 6th 2007, 05:14 AMRuler of HellPolygons Help!
Okay, I've posted after a long time, I know... But I'm here with another doubt.

The ratio between the sides of 2 regular polygons is 4 : 5 and the ratio between the interior angles is 15 : 16. Find the number of sides.

Thanks! - Jan 6th 2007, 05:34 AMCaptainBlack
Let the number of sides of the polygons be and , then the first condition tell you that:

,

and as the interior angle of a ploygon with sides is , the second condition tells us that:

which may be simplified as we know to:

Now we can proceed to solve and , or we can just guess, when we find , .

RonL - Jan 6th 2007, 05:50 AMRuler of Hell
Wait, I'm still a li'l confused. How did you solve equation 1 and 2? Sorry....

- Jan 6th 2007, 05:53 AMCaptainBlack
- Jan 6th 2007, 06:06 AMRuler of Hell
Got it! Yay, thanks a tonne Captain Black... (Though I used 2 different methods, yours and another one) Nonetheless, thanks!