+0  
 
+1
1
331
1
avatar+333 

Quick, how many squares are in an 8x8 chessboard?!

 

Did you answer 64? If so, it's okay. That's technically correct, yet wrong at the same time. If you count including the suares made by squares, however, the number is much bigger.

 

Let's say this is a chessboard:

 

 |||| |||| |||| ||||
|||| |||| |||| |||| 
 |||| |||| |||| ||||
|||| |||| |||| |||| 
 |||| |||| |||| ||||
|||| |||| |||| |||| 
 |||| |||| |||| ||||
|||| |||| |||| |||| 


We can see immediately that there are 64 squares, and more. So how do we calculate for this? The answer is quite simple: 204 or 64+49+36+25+16+9+4+1 squares.

How about a 6x6 square? Well, it's equal to 36+25+16+9+4+1 or 91 squares. Do you see a pattern?

 

Basically, the sum of the squares on an x-by-x grid is equal to:

\(\sum_{i=1}^{x}i^2\)

Wherein x is the side of the grid. For example: we have a 12x12 grid, so the number of squares is:

\(\sum_{i=1}^{12}i^2=12^2+11^2+10^2...+2^2+1\)

\(=144+121+100+81+64+49+36+25+16+9+4+1\)

\(=650\)

 

A 12x12 grid has 650 squares. laugh

off-topic
Mathhemathh  Aug 17, 2017
 #1
avatar
0

how many type of fish species are there that have not been discoved yet?

 

 

cryingcryingHHHHEEEELLLLPPPP!!!!!!!!!! I've been stuck on this question forever.

 

THX SO MUCH!!!!!!!

Guest Aug 17, 2017

7 Online Users

New Privacy Policy

We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive information about your use of our website.
For more information: our cookie policy and privacy policy.