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Math II-A 2.25

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Math II-A 2.25
by Eric Duan - Saturday, December 12, 2020, 9:16 PM

Question 2.25:

Consider the diagram below

How many of the rectangles in the diagram are NOT squares?

I know how to calculate the total number of rectangles in the figure but I’m not sure how to get the total number of squares. 

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Re: Math II-A 2.25
by Duy Duong - Sunday, December 13, 2020, 8:17 AM

I'd help you, but I can't see the diagram.

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Re: Math II-A 2.25
by Eric Duan - Sunday, December 13, 2020, 7:42 PM

I figured it out:

Rectangulars: 7C2 x 6C2=315

Squares: side=1+side=2+side=3+side=4+side=5