Question 541004
<pre>
You can think of the 10 to 19 ratio as a small flag 
with a width of 10 inches and a length of 19 inches.  
We want to know the length of a large flag if the width
of the large flag is 38 inches.

Let the length of the large flag be L.  
We use this proportion equation: 

{{{matrix(1,4,Width, of, small, flag)/matrix(1,4,Length, of, small, flag)}}} = {{{matrix(1,4,Width, of, large, flag)/matrix(1,4,Length, of, large, flag)}}}

            {{{10/19}}} = {{{38/L}}}

Cross multiply:

           10L = 19×38
           10L = 722
             L = {{{722/10}}}
             L = 72.2 inches in length.

Edwin</pre>