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Rule of three - inverse proportion

The rule of  three is a method  to  solve  proportions. If  you have three numbers: a, b, c, such that,   (a/b = c/x) you can calculate the unknown value (x).
Inverse Proportion
When, the increase of a quantity , causes a decrease in the other one , or by the contrary, a decreasing causing the increase in the other one, this is, an inverse proportion. So, the expression: a/b = c/x changes to: (b/a = c/x) because, the numerator becomes denominator and vice versa.
If two workers take 16 days to build 100m of fence, how many days will be spent using four workers?
Problem formulation.
2 workers - 16 days
4 workers -   x days
Full text:Rule of three - inverse proportion.
NOTE: For this application, it is not necessary to replace the numerator by the denominator of the first ratio, because the program automatically performs the change.
Enter the requested data, according to the problem formulation, the results are automatically displayed after you click on "Calculate"

Rule of three - inverse proportion
Decimal places: 
a =  c =  
b =  x  = 


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