I have already blogged about (trying to) teach me Nephew Jason math here and my Great Nephew Justin math here. Now its my Great Niece Jordan's turn.
I was at a dinner with relatives including my 12 year old
great niece Jordan.
There were 10 people at the dinner.
BILL: Jordan, if everyone at this table hugged everyone else,
how many hugs would there be?
JORDAN: If I get it right will you give me a hug?
BILL: I'll give you a hug in any case.
JORDAN: Okay. 10 times 10... so 100.
BILL: Can you hug yourself.
JORDAN: Sure (she then hugs herself).
BILL: For this problem lets assume you cannot hug yourself.
Then how many.
JORDAN: Oh, that changes things. Its 10 times 9... so 90.
BILL: If I hug you and then you hug me, does that count as
one hug or two?
JORDAN: Oh, that changes things. How do you do it?
BILL: Your answer of 90 counted BILL-HUGS-JORDAN and
also JORDAN-HUGS-BILL. The same is true for every pair.
So every pair was counted twice.
JORDAN: So... is the answer (9 times 10)/2 ... 45 ?
BILL: YES! Great. (They hug.)
JORDAN: You're not just a great uncle, you're an AWESOME Uncle!
BILL: And you're an AWESOME Niece!