- #1

powergirl

If there were 15 children in the class, how many total handshakes were there?

:uhh:

- Thread starter powergirl
- Start date

- #1

powergirl

If there were 15 children in the class, how many total handshakes were there?

:uhh:

- #2

- 572

- 3

[tex]\sum_{i=1}^{15}i[/tex]

- #3

powergirl

No.....Slightly wrong

- #4

Hootenanny

Staff Emeritus

Science Advisor

Gold Member

- 9,621

- 6

14.............

- #5

powergirl

14...................?

- #6

- 572

- 3

It's not 120?

- #7

Hootenanny

Staff Emeritus

Science Advisor

Gold Member

- 9,621

- 6

If not the answer must be 210.

- #8

powergirl

no.......sorry

- #9

- 572

- 3

Lol I thought way too fast... 105!

- #10

powergirl

Ya..Now it's Correct........

- #11

Hootenanny

Staff Emeritus

Science Advisor

Gold Member

- 9,621

- 6

hmm, could someone explain this one to me?

Hey dontdistrbmycircles :)

Hey dontdistrbmycircles :)

- #12

powergirl

may I do that?

- #13

- 572

- 3

Keeps going down one because the same person does not shake the same person's hand twice.

- #14

powergirl

The class has 15 children. The first

child shakes hands with the other 14

children. The second child has already

shaken hands with the first child, and so

has to shake hands with only the other 13

children. In this manner, the

second-last child has to shake hands with

only one child, and the last child has

already met all the children. Thus, the

number of handshakes is

14 + 13 + ........ + 2 + 1 = 105.

If there were 15 children in the class,

then there were 105 total handshakes.

- #15

Hootenanny

Staff Emeritus

Science Advisor

Gold Member

- 9,621

- 6

Damn it :grumpy:. Thanks!

- #16

powergirl

Oh....Am I correct?

- Last Post

- Replies
- 24

- Views
- 9K

- Last Post

- Replies
- 19

- Views
- 3K

- Last Post

- Replies
- 16

- Views
- 1K

- Last Post

- Replies
- 3

- Views
- 2K

- Last Post

- Replies
- 12

- Views
- 2K

- Last Post

- Replies
- 5

- Views
- 2K

- Last Post

- Replies
- 7

- Views
- 2K

- Last Post

- Replies
- 7

- Views
- 977

- Last Post

- Replies
- 6

- Views
- 778

- Last Post

- Replies
- 32

- Views
- 5K