# Brain Teaser 商业头脑

Brain Teaser

Mr. Ong, the boss, is a shoe dealer. A particular pair of shoes costs him \$20 & selling for \$30.

One customer came & gave a \$50 note to buy a pair of the said shoes. The boss didn’t have small change, so went to the neighbour to get the \$50 small change.

After the sale, the neighbour realised the \$50 is a fake one & the boss has to pay back the neighbour.

Question: How much is the boss’s total loss?

（这道题不简单，100个人有99人会算错）
(This question is not that simple. 99 out of 100 will get it wrong)

So how much is the total loss?

Ans: \$100 / \$40 / \$90 ?

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