I don't recall doing/learning this type of problem or anything at all similar to it when I was in 3rd grade.

New math out since then, they just discovered it.

I wasn't involved in a lot of garage sales back in those days.

FAX

$3

This happen on an episode of Sanford & Son. True story :-)

He would have been out of $79 for the change, $100 for replacement of the faked bill and $18 worth of merchandise. All he would have gained was the $21. $158.

Thats the same answer Lamont gave Fred







BIG DUMMY :D

You can't count both the $79 and the $100 as costs. The neighbor gave him the $79, (as well as another $21).

Neighbor gave him $100 in increments that break down to $79 and $21, he gave $100 back to the neighbor. The transactions with the neighbor are a wash, and should be ignored. Its easier to assume he had $79 in his pocket when the guy bought the sweater.

The answer is $28

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You are making this way too hard. Assign the fake bill a value of zero.

He received a fake bill. ($0)
He gave away a sweater (minus one sweater)
He traded fake bill for $100 (plus $100)
He gives the customer change (minus $79)
He reimburses neighbor (minus $100)

Add it up: $0 + $100 - $79 - $100 - sweater

He is out $79 plus whatever value you assign to the sweater.

Why would the neighbor tell Fax the bill was counterfeit? He's up a sweater and $79 vs. his original position.

$2145

The buyer and neighbour are different people

Then why did the neighbor get $100 back??

Yes I know. I jumped in the shower and all I could do was think about this poor man and his sweater. I came to the $79 answer myself and hoped to jump on the website, erase my post and escape without penalty.

Alas that isn't the case.