Chapter 6.5, Problem 3ACYP

To determine

To Find: The cost of 8 DVDs.

Answer to Problem 3ACYP

The cost of 8 DVDs is $\$79.12$

Explanation of Solution

Given information:

Cost of 5 DVDs is $\$49.45$

Concept and Formula Used:

Use the concept of direct variation and ratio and proportion.

Calculation:

It is given that cost of 5 DVDs is $\$49.45$

First find the cost of 1 DVD

Cost of 1 DVD is $=\$\frac{49.45}{5}$

Let the cost of 8 DVDs be $x\$$ .

Therefore cost of 1 DVD is $=\$\frac{x}{8}$

As the cost for one DVD remains same. On equating

  $\$\frac{49.45}{5}=\$\frac{x}{8}$

Cross multiply

  $\begin{array}{l}49.45\times 8=x\times 5\\ 395.6=5x\\ \text{Divide both sides by 5}\\ \frac{395.6}{5}=\frac{5x}{5}\\ 79.12=1x\\ \text{or }x=79.12\end{array}$

Conclusion:

The cost of 8 DVDs is $\$79.12$