Beginning Mathematics/Rate and ratio

Ratio: a term of math in which you have two numbers and you compare them. For example, if you had six pencils and four erasers, the ratio of pencils to erasers would be- 6:4 or six to four. Also, equivalent ratios are if you have two different ratios with two different second terms, like: 6:4 and 3:7, you could find out which one is greater by doing the following...
 * 1) You multiply 6x7, which is 42, then you know your first term is 42.
 * 2) multiply 4x7 to get 28, so your full first ratio would be 42:28.
 * 3) multiply 3x4 to get an answer of 12. Your first term on your SECOND ratio would be 12.
 * 4) multiply 7x4 to get 28. Your full second ratio will be 12:28.

So therefore, the two ratios are equivalent, or the same as, 42:28 and 12:28. That would mean your greater ratio is the first ratio, 42:28, because 42 is larger/greater than 12.