Difference between revisions of "2024 DMC Mock 10 Problems/Problem 14"
Pateywatey (talk | contribs) (Created page with "First, <math>a=2</math>, since if <math>a\geq 3</math>, then <cmath> \frac{1}{a} + \frac{1}{b} + \frac{1}{c} < \frac{1}{3} + \frac{1}{3} + \frac{1}{3} = 1</cmath> and if <ma...") |
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<cmath> \frac{1}{a} + \frac{1}{b} + \frac{1}{c} < \frac{1}{3} + \frac{1}{3} + \frac{1}{3} = 1</cmath> | <cmath> \frac{1}{a} + \frac{1}{b} + \frac{1}{c} < \frac{1}{3} + \frac{1}{3} + \frac{1}{3} = 1</cmath> | ||
− | and if <math>a=1</math> then the expression is greater than one. The problem then reduces to <math>\frac{1}{b}+\frac{1}{c} = \frac{1}{2}. | + | and if <math>a=1</math> then the expression is greater than one. The problem then reduces to <math>\frac{1}{b}+\frac{1}{c} = \frac{1}{2}</math>. |
− | Using a similar process, we find < | + | Using a similar process, we find <math>b=3</math> and <math>c=6</math>, so the only solution is <math>(a,b,c) = (2,3,6)</math>. Therefore the answer is <math>2+3+6=\boxed{11}</math>. |
Latest revision as of 12:15, 22 December 2024
First, , since if , then
and if then the expression is greater than one. The problem then reduces to .
Using a similar process, we find and , so the only solution is . Therefore the answer is .