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## Question

Mystery Operation II

Finally: a message was received from outer space!

At first glance it seems that it contains a sequence of 9 numbers coded as beeps and pauses. Large pauses group 3 numbers together, suggesting a relation might exist between them.

```
4 */* 2 = 5

12 */* 17 = 28

30 */* 10 = 36

```
Scientists immediately start transmitting our standard welcome message containing mathematical constants. For a while it looks as though no one listening until suddenly a second message is received. This message repeats only 2 numbers for a long period of time.
```
48 */* 73

```

Maybe we're supposed to respond to it in order to make contact. Can you help scientists figure out what we should answer?

Edited by araver

## 41 answers to this question

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```
4 */* 2 = 5

12 */* 17 = 28

30 */* 10 = 36

100 */*	93 = 186

42 */* 35 = 72

100 */* 21 = 116

12 */* 11 = 22

19 */* 29 = 48

41 */* 31 = 72

------------------

48 */* 73 = ?

```

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```
4 */* 2 = 5

12 */* 17 = 28

30 */* 10 = 36

100 */*	93 = 186

42 */* 35 = 72

100 */* 21 = 116

12 */* 11 = 22

19 */* 29 = 48

41 */* 31 = 72

11 */* 18 = 28

------------------

48 */* 73 = ?

```

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...120

Indeed it does. Can you explain why?

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Would you like me to? Got another lined up? In the vain of octopuppy, here's a fun one --> 238 */* 222 = 444

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Would you like me to? Got another lined up? In the vain of octopuppy, here's a fun one --> 238 */* 222 = 444

Sorry, no other mystery op lined up at the moment, been busy with preparing and now hosting a new mafia game. Plus octopuppy's CtC.

Leaving it unsolved so others can enjoy then!

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any more clues?

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```
4 */* 2 = 5

12 */* 17 = 28

30 */* 10 = 36

100 */*	93 = 186

42 */* 35 = 72

100 */* 21 = 116

12 */* 11 = 22

19 */* 29 = 48

41 */* 31 = 72

11 */* 18 = 28

238 */* 222 = 444

------------------

48 */* 73 = ?

```

As he solved it, I did not post any more clues, but if anyone still wants to solve it, I will post more.

Edited by araver

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The solution was never explained and I am sadly stumped. I have a theory about varrying bases based on the given numbers but still no solution.

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The solution was never explained and I am sadly stumped. I have a theory about varrying bases based on the given numbers but still no solution.

You are right, the solution was not explained and the challenge is still open.

I'll continue to post examples - adding one now. Also, if you want to test your theory you can tell me a pair "(a,b)" and I will tell you "a */* b"

```
4 */* 2 = 5

12 */* 17 = 28

30 */* 10 = 36

100 */*	93 = 186

42 */* 35 = 72

100 */* 21 = 116

12 */* 11 = 22

19 */* 29 = 48

41 */* 31 = 72

11 */* 18 = 28

238 */* 222 = 444

11 */* 21 = 30

------------------

48 */* 73 = ?

```

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Adding another example to the challenge:

```
4 */* 2 = 5

12 */* 17 = 28

30 */* 10 = 36

100 */*	93 = 186

42 */* 35 = 72

100 */* 21 = 116

12 */* 11 = 22

19 */* 29 = 48

41 */* 31 = 72

11 */* 18 = 28

238 */* 222 = 444

11 */* 21 = 30

9 */* 13 = 20

------------------

48 */* 73 = ?

```

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How about 1 */* 0, 10 */* 0 and 1 */* 1?

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How about 1 */* 0, 10 */* 0 and 1 */* 1?

Hi k-man. I've added one of the three in the table below.

```
4 */* 2 = 5

12 */* 17 = 28

30 */* 10 = 36

100 */*	93 = 186

42 */* 35 = 72

100 */* 21 = 116

12 */* 11 = 22

19 */* 29 = 48

41 */* 31 = 72

11 */* 18 = 28

238 */* 222 = 444

11 */* 21 = 30

9 */* 13 = 20

1 */* 1 = 2

------------------

48 */* 73 = ?

```

EDIT: missed the example.

There's a catch: x */* 0 does not make sense i.e. is undefined.

I could define it just for the sake of making it a complete operation, but it would not be fair.

Edited by araver

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that x */* x = 2*x ?

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that x */* x = 2*x ?

Not always. E.g. 4 */* 4 = 6.

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120 as plainglazed has already revealed, so I will offer 112 */* 100 = 206 as proof of understanding.

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120 as plainglazed has already revealed, so I will offer 112 */* 100 = 206 as proof of understanding.

Correct. Proof accepted

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