Question 1207685
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The inverse of a modulo 44 is b. What is the inverse of 9 modulo 10?
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<pre>
Inverse of 9 modulo 10 is an integer number  1 <= n <= 9  such that the product

    n*9 is equal to 1 modulo 10.


As soon as you pronounce these words mentally (as the definition), the answer just should be in your mind:


    +-----------------------------------------------------------+
    |    the inverse of 9 modulo 10 is the number 9 modulo 10.  |
    +-----------------------------------------------------------+


Indeed, 9*9 = 81, which is equal to 1 modulo 10.


<U>ANSWER</U>.  The inverse of 9 modulo 10 is the number 9 modulo 10.
</pre>

Solved.



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This problem consists of two statements.


Of these two statements, &nbsp;the first one does not bring any relevant information;
therefore, &nbsp;having sanity in the skull, &nbsp;we should ignore this first statement 
(by pointing that it is non-sensical).


The second statement brings the question and makes sense &nbsp;(even if consider it 
independently of the first statement).


So, &nbsp;I ignore first statement &nbsp;(as if it is empty and as if it does not exist) 
and react to the second statement - it is precisely what &nbsp;I &nbsp;do.




&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;************************************************

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In this problem formulation, the first statement

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;does not carry any information, &nbsp;is not necessary 

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;and interferes with understanding the rest of the task.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;************************************************