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**mathstudent2000****Member**- Registered: 2013-07-26
- Posts: 79

1. How many sets of 3 primes sum to 20?

2. An old book listed that 72 turkeys were bought for $\square.\square\square each, at a total cost of $\square 67.9\square. What was the cost of each turkey, if each \square stands for a digit that was unreadable in the old book?

Note: The \square digits are not all the same.

3. A number has three distinct digits. The sum of the digits equals the product of the digits. How many three-digit numbers satisfy this condition?

Genius is one percent inspiration and ninety-nine percent perspiration

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,522

Hi

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,366

Hi;

2)

What does \square mean?

The only solution to the problem as you have written it is:

72 x 5.11 = 367.92

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,522

Yes, I agree. That is the only possibility.

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

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**mathstudent2000****Member**- Registered: 2013-07-26
- Posts: 79

ok

it means a box in which a unknown number is placed

Genius is one percent inspiration and ninety-nine percent perspiration

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,366

It is the only answer, it was derived in 2 ways.

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**mathstudent2000****Member**- Registered: 2013-07-26
- Posts: 79

ok got it

Genius is one percent inspiration and ninety-nine percent perspiration

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