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Ratio and proportion

Date: Mon, 5 Dec 1994 19:27:47 -0600 (CST) 
From: Thelma Ann Gonzalez
Subject: Math Help

I am a student taking Geometry.  I need extra help in ratio and proportion.   
I would appreciate it if you would write back with examples.     

Adriana Gonzalez  

Date: Mon, 5 Dec 1994 22:08:58 -0500 (EST)
From: Dr. Sydney
Subject: Re: Math Help

Dear Adriana:

Thanks for writing Dr. Math!  I'm not sure what kind of examples of
ratios you were thinking of, but I'll throw out a few for you to think
about.  Putting two numbers in a ratio gives you a sense of the relative
sizes of two numbers.  For instance if I want to know the ratio of 200 to
100 I say it is 200/100 = 2.  That means 200 is twice the size of 100.  

Proportionality is very related to ratios.  If I have a triangle with sides
3, 4, and 5, and I have another triangle with sides in proportion to the
first triangle, the second triangle's sides must have the same ratio with
one another as in the first triangle.  So, for instance, a triangle with
sides 6, 8, 10 is proportional to the triangle of sides 3, 4, 5 because its
sides are exactly twice as big as the first triangle.

I hope this helps answer your question.  Please feel free to write
back if you have any other questions.  

--Sydney, Dr. Math
Associated Topics:
High School Geometry
High School Triangles and Other Polygons
Middle School Geometry
Middle School Ratio and Proportion
Middle School Triangles and Other Polygons

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