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I appreciate the help!

 May 30, 2016
 #1
avatar
0

The following values appear to work:

x=5, y=49, z=97

 

Alan: Please verify this. Thanks.

 May 30, 2016
 #2
avatar+23248 
0

I agree with guest's answer of:  x = 5, y = 49, and z = 97; this answer checks!

My analysis is this (but, I have no idea whether or not it is a correct procedure or only a lucky procedure):

 

1/x - 1/(xy) - 1/(xyz)  =  19/97     with x < y < z

 

First find the sum of the left-side using the common denominator of xyz:

 

1(yz) / (xyz) - 1(z) / (xyz) - 1 / (xyz)  =  19 / 97   --->   (yz - z - 1) / (xyz)  =  19/97

 

The denominator of the left side has three factors; the denominator of the right side has only one factor, the prime number 97.  It needs two more factors. Since z is the largest of the three factors, claim that  = 97 and multiply the right hand side by xy/xy     --->     (yz - z - 1) / (xyz)  =  19xy / (97xy)

 

Claim that the numerators are equal:     --->     yz - z - 1  =  19xy

and claim that the denominators are equal:     --->     xyz  =  97xy     with z = 97.

 

Since z = 97     --->     yz - z - 1  =  19xy     --->     97y - 97 - 1  =  19xy

                                                                   --->     97y - 98  =  19xy

                                                                   --->     97y - 19xy  =  98

                                                                   --->     y(97 - 19x)  =  98

Since the factors of 98 are 2 and 49:         --->     y(97 - 19x)  =  2·49

So, if we are dealing with whole numbers,

either y = 2 or y = 49 (2 won't work           --->     49(97 - 19x)  =  2·49

because y > x  and x = 1 doesn't               --->          97 - 19x  =  2

work).                                                         --->                -19x  =  -95 

                                                                  --->                     x  =  5

 May 30, 2016
 #3
avatar+33616 
0

Yes, I get x=5, y=49, z=97

 

There is another triple that results in 19/97, namely x=5, y=97, z=1; however, this doesn't satisfy the condition x<y<z

.

 May 31, 2016

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