Question 1111828
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The problem can be easily solved MENTALLY.


<pre>
Since the frame is of uniform width, the difference of exterior dimensions of the frame is the same as the difference of dimensions 

of the picture, i.e. 10 - 8 = 2 inches.


So, to solve the problem, you need to decompose the number of 224 into the product of two factors with the difference of 2 between them.  It is


224 = 225 - 1 = {{{15^2-1}}} = (15-1)*(15+1) = 14*16.


From this decomposition,  14 = 8 + 2w  and hence  w = {{{(14-8)/2}}} = 3 inches.
</pre>

Solved.


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