This problem is making the rounds on Facebook and Twitter with thousands of people arguing about the correct answer. How smart are you? A guy walks into a store and steals a $100 bill from the register without the owner's knowledge. He then buys $70 worth of goods using the $100 bill and the owner gives $30 in change. How much money did the owner lose? $30, $70, $100, $130, $170, or $200?

My blog post for this video
http://wp.me/p6aMk-53H

Sources
Thanks to Eric for sending me this problem by email.

One version of the problem on Facebook with 20,000 shares:
https://m.facebook.com/story.php?story_fbid=1254756407914475&id=100001403825442

Sorry I can't reply to your emails about this! I have been getting a lot of emails with alternate answers and asking to find the mistake in reasoning. I've explained all I can in this post and the video, so if you still don't agree you'll have to ask someone else.

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