The number of pencils sold varies directly as the cost. If 5 pencils cost \( \$ 0.45 \), find the cost of 7 pencils. Cost: \( \$ \) type your answer... desmos | Virginia | Grades 6-8 Version

To find the cost of 7 pencils, we start by determining the cost per pencil based on the initial information given. If 5 pencils cost \( \$0.45 \), the cost per pencil is \( \frac{0.45}{5} = 0.09 \) (or 9 cents). Now, for 7 pencils, the cost would be \( 7 \times 0.09 = 0.63 \). Hence, the cost of 7 pencils is \( \$0.63 \). Now, let’s take a fun dive into pencil history! Did you know the modern pencil with eraser was invented in the 1850s? Before that, people used to erase their mistakes with rags or bread! Isn’t it fascinating how something as simple as a pencil has evolved over the years to make our lives easier? And if you're looking to get creative while also sharpening those problem-solving skills, try visualizing relationships like this one with graphs or charts! They can help you see the patterns of direct variation more clearly. Plus, a common mistake is forgetting to first find the unit cost. Always double-check your calculations to avoid a slip-up next time!