- Identify the scaling factor between the denominators: \(39 \div 13 = 3\).
- Multiply the numerator by the same scaling factor: \(-8 \times 3 = -24\).
- Conclude that the equivalent fraction is \(\frac{-24}{39}\).
- Final answer: \(\boxed{-24}\).
Explanation
- Problem Analysis
We are given the equation \(\frac{-8}{13} = \frac{x}{39}\). Our goal is to find the numerator \(x\) that makes the two fractions equivalent. To maintain equivalence, if we multiply the denominator of a fraction by a certain number, we must multiply its numerator by the same number.
- Solving for x
First, we observe the relationship between the two denominators, \(13\) and \(39\). We determine the factor by which \(13\) was multiplied to get \(39\):
\[39 \div 13 = 3\]
Thus, the denominator is scaled by a factor of \(3\). To keep the fraction equivalent, we must multiply the numerator \(-8\) by this same factor:
\[x = -8 \times 3\]
Performing the multiplication, we find:
\[x = -24\]
- Conclusion
We have found that \(x = -24\). We can check the equivalence of the fractions by verifying:
\[\frac{-24}{39} = \frac{-24 \div 3}{39 \div 3} = \frac{-8}{13}\]
Since the fractions are equivalent, our solution is correct. The value of the numerator is \(\boxed{-24}\).
Examples
Equivalent fractions are used in many real-life situations, such as cooking or managing shared resources. For instance, if a recipe calls for \(\frac{8}{13}\) of a cup of a specific ingredient, but you only have measuring cups marked with 39ths, you would need to calculate that you need \(\frac{24}{39}\) of a cup. Understanding how to scale fractions helps ensure that ratios remain constant, whether you are scaling a recipe, adjusting proportions for a design project, or distributing workloads fairly.