SAT Math Help for a Girl who wants to learn!

Test Preparation SAT Preparation
1

<p>Hi everyone! I am trying to self study for the SAT and I have a math question. I am using Dr. Chung's SAT math guide and need a further explanation of a problem. It has to do with "Ratio of Similar Figures." </p>

<p>The question is..</p>

<p>"The figure above, the radius of a larger circle is 5/2 times the radius of the smaller circle. What fraction of the larger is the shaded region. </p>

<p>The ratio of the length is: 5/2
The ratio of the area= 5^2/2^2= 25k/21K</p>

<p>My question is, where do the K's come from?</p>

<p>If anyone can help me, that would be great!</p>

2

<p>k can be any integer; remember, the question says that the radius of the larger circle is 5/2 times the radius of the smaller circle, and the radius of one circle can be any number. Thus, because the RATIO of the lengths is 5/2, 5k/2k(for the line) => 25k/21k(for the area) is true because we the ks cancel out.</p>

3

<p>k is arbitrary; for example, you can assume k = 1.</p>

4

<p>Thank you!!!</p>