algebraic expression?

Question

The following tower has 5 tiles along its base and 5

rows of tiles. How many tiles will be required to

build a tower like this with 25 tiles along its base

and 25 rows of tiles? Write an algebraic expression

for the number of tiles in a tower with n tiles along

its base and n rows of tiles. The example given has 5 tiles on first row, 4 on 2nd, and so forth. Please help!!!

Answer 1

Favorite Answer

You've got a sum of squares going on. The formula, where n is the base (& row) of the bottom square of tiles, is:

n(n + 1)(2n + 1)/6