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Zero. April 28th 2012 10:12 AM

Oh a math question...?
 
*awkward look* urmmmm can anyone help me with this math question?

Whats the percentage increase in the area of the circle if the radius of the circle is increased by a)10%
b)50%
c) 100%

I've tried other sites but they keep giving different answers! argh!
I got:

a) 21%
B) 125%
c)1000%

the answer for c sounds CRAZYYYYYYYYYY

Music April 28th 2012 04:01 PM

Re: Oh a math question...?
 
The easiest way to do this is to choose a base circle for all your math. Let's say your base circle has a radius of 10 and an area of 314

A 10% increase in radius is going to make it 11. 11x11x3.14=380
To get % you can do ((380-314)/314)x100 which shows that this is a 21% increase

A 50% increase in radius makes it 15. 15x15x3.14=706.5
((706.5-314)/314)x100=125
So the answer to b is 125%

A 100% increase in radius makes it 20. 20x20x3.14=1256
((1256-314)/314)x100=300
So the answer to c is 300%

You really shouldn't look for answers on the internet, you don't learn the lesson intended which means you may as well not do it. When you don't know how to do something your best bet is to ask your teacher or another person in your class.


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