Question

six is called a perfect number because its factor {not including 6} adds up to itself, i.e. 1+2+3=6 Find all the perfect numbers between 20 and 30. @mkerr017 @zepdrix @aum

Answer 1

\[\Large\rm 20:~1+2+4+5+10\ne 20\]Hmm that one's no good, yah? :d
Just trial and error it looks like c:

Answer 2

yeah, i think you can do this one on your own, you just don't want to :D

Answer 3

Ooo I found one!! c:
I think there is only 1 number that will work.
Keep looking choo!

Answer 4

i dont know how to work it out im only in grade 5

Answer 5

seriously?! I just learned a lot of this stuff last year as a freshman 0.o

Answer 6

i still need help, this is what this site is for, isnt?

Answer 7

Yeah, sorry, that was rude of me:/

Answer 8

Do you know the factors of 22? :)
Numbers that multiply to give you 22.

Answer 9

it okay!

Answer 10

1 and 22
2 and 11

I think those are all the factors of 22, yes?

Answer 11

11?@zepdrix

Answer 12

2 x 11 = 22, yes? 0_o

Answer 13

think so

Answer 14

hey choka choka :)

Answer 15

We don't include the number itself, so we exclude the 22.
Do the other factors add up to 22?

1 + 2 + 11 = ?

Answer 16

no

Answer 17

Ok great, so we can cross 22 off of our list c:

Answer 18

23 is a prime number. So let's skip that one.
The only other factor besides 23 is 1.
So 1 does not add up to 23 >.<

Answer 19

Can you figure out the factors of 24? There are a lot of them!

Answer 20

1,2,3,4,6,7,8,12,24?

Answer 21

Mmmm yah I think that's all of them! c:
Exclude 24, do the others add up to 24?

Answer 22

no

Answer 23

Darn we gotta keep looking D:
Keep trying choo choo!

Answer 24

what am i looking for, i forgot?

Answer 25

For the factors of the number to add to the number.
(excluding itself in the addition).

Answer 26

So when they showed you the example with 6...
the factors of 6 are
1,2,3,6

We check to see if all the factors (besides the 6) add up to 6.
1+2+3 = 6

Answer 27

There is another number that also does this in the 20's somewhere.

Answer 28

ok