Question

If you save one penny on January 1, two pennies on January 2, three pennies on January 3, and continue this pattern for one year (not a leap year), what will be the value of your entire savings, in dollars, at the end of that one year? Express your answer as a decimal.

Answer 1

I think you know the answer...........you just don't know the number right?

Answer 2

The answer is
Total money (in pennies) = 1+2 +3 +4+..........................+364+365
right

Answer 3

Yes

Answer 4

What equation would i use to figure this out?

Answer 5

I think this involves the 365! equation...just keep adding :P

Answer 6

That's a lot of adding though! D:

Answer 7

You can do this with Gaussian addition http://mathcentral.uregina.ca/QQ/database/QQ.02.06/jo1.html, or do it as an arithmetic sequence

Answer 8

Have you learned arithmetic sequences...?

Answer 9

Yes, I've learned about them. I just didn't remember which formula to use. I will try the Gaussian addition though.

Answer 10

It's 66,795 pennies, now you just have to decide how many dollars thats worth :)

Answer 11

sry I was away:
let Total Amount be S
So S = 1+2+3+................................+364+365
now reverse it
S = 365 +364 +..............................+2+1
Add them up and see........you don't need any formula for this :0

Answer 12

If you use arithmetic sequences, you'll get the gaussian addition formula anyway

Answer 13

Add S forward and S reverse

Answer 14

its 66795 pennies, move the decimal place voer 2 and you get 667.95 dollars.

Answer 15

I used the Gaussian addition formula and I got 66,795 pennies. So I guess $667.95 is the answer?

Answer 16

yes tegiebear :D

Answer 17

Okay, thank you guys very much! :)

Answer 18

S = 1 + 2 + 3 + 4 +.....................................364 + 365
S =365+ 364+ 363+362+.........................................2 + 1
Adding
2S = 366 + 366 + 366 +...................365 times
2S = 365*366
S = 365*366/2
Thought this trick will help you

Answer 19

@atlas the link i first posted shows that exact method (Gaussian addition)

Answer 20

ah sry i didn't see it............... :P

Answer 21

no prob, plus it was only using 1 to 100 not 1 to 365

Answer 22

oic