SOLUTION: How many boxes are there in a pyramid that has a base of 100 boxes? And why?

Algebra ->  Functions -> SOLUTION: How many boxes are there in a pyramid that has a base of 100 boxes? And why?      Log On


   

Question 612912: How many boxes are there in a pyramid that has a base of 100 boxes? And why?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Base has 100

1st level has 81 (since 10 - 1 = 9 and 9^2 = 81)

2nd level has 64 (since 8^2 = 64)

etc etc

So we're adding the squares

100+81+64+49+25+16+9+4+1

or

1+4+9+16+25+36+49+64+81+100

to get

100+81+64+49+25+16+9+4+1 = 349

or

1+4+9+16+25+36+49+64+81+100 = 349

So there are 349 boxes total.