Chapter 6.6, Problem 30SR

To determine

To Solve: The equation $\frac{4}{10}=\frac{8}{a}$

Answer to Problem 30SR

  $a=20$

Explanation of Solution

Given information:

The equation $\frac{4}{10}=\frac{8}{a}$

Concept and Formula Used:

To solve the equation bring variable to one side and constant to other side and use cross multiplication.

Calculation:

The given equation is $\frac{4}{10}=\frac{8}{a}$

Cross multiply

  $\begin{array}{l}\frac{4}{10}=\frac{8}{a}\\ 4\times a=8\times 10\\ 4a=80\\ \text{Divide both side by 4}\\ \frac{4a}{4}=\frac{80}{4}\\ 1a=20\\ a=20\end{array}$

Conclusion:

  $a=20$