SOLUTION: What are 3 unequal positive rational numbers a, b, & c for which a+b+c=1/(a+b+c)

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Question 522562: What are 3 unequal positive rational numbers a, b, & c for which a+b+c=1/(a+b+c)
Answer by Edwin McCravy(20086) About Me  (Show Source):
You can put this solution on YOUR website!
a+b+c = 1%2F%28a%2Bb%2Bc%29

Multiply both sides by (a+b+c)

(a+b+c)² = 1

Take positive square roots of both sides:

a+b+c = 1

So we just need three fractions that have sum = 1

To do that take any 3 integers, say 1, 4 and 5

Put their sum over itself and that will equal 1

%281%2B4%2B5%29%2F%281%2B4%2B5%29 = 1 

Add the terms in the denominator but leave the numerator
terms added:

%281%2B4%2B5%29%2F10 = 1

Write as the sum of three fractions:

1%2F10 + 4%2F10 + 5%2F10 = 1

Reduce any that will reduce:

1%2F10 + 2%2F5 + 1%2F2 = 1

So  a=1%2F10, b=2%2F5, c=1%2F2

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There is no end to the number of different possibilities following that recipe:

%282%2B3%2B4%29%2F%282%2B3%2B4%29 = %282%2B3%2B4%29%2F9 = 2%2F9 + 3%2F9 + 4%2F9 = 2%2F9 + 1%2F3 + 4%2F9 = 1

%281%2B2%2B3%29%2F%281%2B2%2B3%29 = %281%2B2%2B3%29%2F6 = 1%2F6 + 2%2F6 + 3%2F6 = 1%2F6 + 1%2F3 + 1%2F2 = 1

%281%2B2%2B5%29%2F%281%2B2%2B5%29 = %281%2B2%2B5%29%2F8 = 1%2F8 + 2%2F8 + 5%2F8 = 1%2F8 + 1%2F4 + 5%2F8 = 1

Edwin