# "SIMPLE" ARITHMETIC

### Re: "SIMPLE" ARITHMETIC

The question here is ….
The 3 students spent, after the discount, a total of \$27.00 for the 3 fountain pens. The shop assistant pocketed \$2.00 for himself. 27 + 2 = 29 …. Where has that \$1.00 gone to?

The riddle does not support answers such as 3 subtract 2; or 30 – (27+2); although they are mathematically correct.

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the answer should be

1. the money spent = the money received

a total of 27 (three students spent) = the total of 25 (the shop owner received) + 2 ( the shop assitant pocketed)

2. \$30 is just a misleading figure.
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### Re: "SIMPLE" ARITHMETIC

alpha123 寫道：
the answer should be

1. the money spent = the money received

a total of 27 (three students spent) = the total of 25 (the shop owner received) + 2 ( the shop assitant pocketed)

2. \$30 is just a misleading figure.

Hi Guru

Spot on! Old ginger taste spicier. Let me do the explanation, and correct me where I go wrong.

First of all, the riddle attempts to deviate from the actual answer by saying “where has that \$1.00 gone to?” Secondly, it reinforces that digression by misguiding those who attempt, that answers such as 3 subtract 2; or 30 – (27+2) are not acceptable.

Notice the word SIMPLE in inverted comas. Therefore a simple equation is the solution. As you know equations are to show the equality of two expressions containing one or more variables. For example, given any value of x, it is always true that x − x = 0.

In this case, 30 – 3 = 27 (representing the money the students spent); and 25 + 2 = 27 (representing those who received monies). As such 27 – 27 = 0. Hence there is no ‘loss’ in the “game.”

Another method to solve this riddle is by using simple (again SIMPLE here) accounting principle; i.e. Debit and Credit.

DEBIT

To purchase of pens \$30.00
To discount received ( 3.00)
Balance \$27.00

CREDIT

By sale of pens \$30.00
By discount allowed ( 5.00)
By shop assistant 2.00
Balance \$27.00

Thanks for responding. BTW, what about the solution for that OPTIMIZATION thing? Cheers!

________
hAvE fUn

...That which is striking and beautiful is not always good. That which is good is always beautiful.
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