# Relatively simple question but i just cant get it !

• Sep 2nd 2010, 08:34 PM
liukawa
Relatively simple question but i just cant get it !
Hi guys.

Am stuck with a question which looks relatively easy.

But i just simply cant get the answer !

need help urgently as i need to submit this to my tutor by today else i am toast meat !!! (Punch)

Attachment 18808
• Sep 2nd 2010, 09:00 PM
undefined
Quote:

Originally Posted by liukawa
Hi guys.

Am stuck with a question which looks relatively easy.

But i just simply cant get the answer !

need help urgently as i need to submit this to my tutor by today else i am toast meat !!! (Punch)

Attachment 18808

The capital pi confused me a bit, thought it was a stray character typo, should be lowercase pi.

Also don't make the same (reading) mistake I did and think pi*y is the volume of the sphere instead of the cylinder!

Trick is to draw the radius of the sphere and find a right triangle, and use what you know about right triangles.
• Sep 2nd 2010, 10:33 PM
liukawa
Quote:

Originally Posted by undefined
The capital pi confused me a bit, thought it was a stray character typo, should be lowercase pi.

Also don't make the same (reading) mistake I did and think pi*y is the volume of the sphere instead of the cylinder!

Trick is to draw the radius of the sphere and find a right triangle, and use what you know about right triangles.

Actually i have already worked backwards and i realise that r^2 = 25-1/4h^2.

And i tried to form a right angle triangle with r and h/2 and by working backwards using pythogras theorem, i know that the hypontenus is 25. However, I just simply dont get it why is the hypontenus of this right angle triangle 25.
• Sep 2nd 2010, 10:45 PM
undefined
Quote:

Originally Posted by liukawa
Actually i have already worked backwards and i realise that r^2 = 25-1/4h^2.

And i tried to form a right angle triangle with r and h/2 and by working backwards using pythogras theorem, i know that the hypontenus is 25. However, I just simply dont get it why is the hypontenus of this right angle triangle 25.

The hypotenuse is 5. It's the radius of the sphere, given in the problem statement.
• Sep 2nd 2010, 10:58 PM
liukawa
Oh ya !

Thanks dude !

u are awesome !