The 99th pyramidal number is 328,350. That would make quite a stack of basketballs! What number must you add to 328,350 to get the 100th pyramidal number?
a. 100
b. 328,350
c. 10,000
d. 55
e. 1000

Question

The 99th pyramidal number is 328,350. That would make quite a stack of basketballs! What number must you add to 328,350 to get the 100th pyramidal number?
a. 100
b. 328,350
c. 10,000
d. 55
e. 1000

fibonaccichick666 · Answer

What have you tried?

clamin · Answer

Im actually confuse of this question because theres no number of 100th

fibonaccichick666 · Answer

Well, you have a formula to calculate pyramidal numbers right?

clamin · Answer

Im not sure

fibonaccichick666 · Answer

ok, let's start with, what is a pyramidal number?

clamin · Answer

328,350

fibonaccichick666 · Answer

no, my bad, I mean, what is the definition of a pyramidal number?

clamin · Answer

Pyramidal sequence isna sequence of numbers that are the sum of perfect squares.

fibonaccichick666 · Answer

ok, that is a version. check out this one, specifically look at the picture to get an understanding of the concept in 3D http://mathworld.wolfram.com/SquarePyramidalNumber.html

clamin · Answer

I cant open it I thibk its becuase im only using my phone

fibonaccichick666 · Answer

ok, well if you can, google "wolfram square pyramidal number"

fibonaccichick666 · Answer

it will make a lot more sense if you can visualize this concept

inkyvoyd · Answer

hint: pyramidal numbers are formed by adding consecutive perfect squares. as in 1+4+9+16+25+36+...
That should be enough to get you to the answer.

clamin · Answer

is it 100

clamin · Answer

@inkyvoyd

fibonaccichick666 · Answer

not 100

clamin · Answer

10,000

fibonaccichick666 · Answer

maybe take a look at one of the other questions on this you posted before for the sequence

fibonaccichick666 · Answer

and yes. 100^2

inkyvoyd · Answer

1+4+9+16+25+36+...
$1+2^2+3^2+4^2+5^2+6^2+...+99^2+100^2$