Examples of surface area in daily life for Grade 7 students

📚 Quick Study Guide

• 📐 Surface Area Definition: Surface area is the total area of all the surfaces of a 3D object. Think of it as the amount of material needed to cover the object.
• 🧊 Common Shapes: We often calculate surface area for cubes, rectangular prisms, cylinders, and spheres.
• 🔢 Formulas to Remember:
  • 🟥 Cube: $6s^2$ (where $s$ is the side length)
  • 📦 Rectangular Prism: $2(lw + lh + wh)$ (where $l$ is length, $w$ is width, and $h$ is height)
  • 🛢️ Cylinder: $2\pi r^2 + 2\pi rh$ (where $r$ is the radius and $h$ is the height)
• 💡 Real-World Applications: Calculating paint needed for a wall, wrapping paper for a gift, or the material to make a box all involve surface area.

🧪 Practice Quiz

1. What is an example of calculating surface area in daily life?
   1. A. Measuring the volume of water in a bottle.
   2. B. Calculating the amount of wrapping paper needed for a gift.
   3. C. Finding the perimeter of a garden.
   4. D. Determining the weight of a book.
2. Imagine you're painting a rectangular box. What do you need to know to calculate the surface area you'll paint?
   1. A. Only the length of the box.
   2. B. Only the height and width of the box.
   3. C. The length, width, and height of the box.
   4. D. Only the volume of the box.
3. A can of soup is shaped like a cylinder. What parts of the can do you need to measure to calculate its surface area?
   1. A. The length and width.
   2. B. The radius and height.
   3. C. The diameter and volume.
   4. D. The weight and height.
4. If you're making a cardboard box, what does the surface area tell you?
   1. A. The amount of space inside the box.
   2. B. The amount of cardboard needed to make the box.
   3. C. The weight the box can hold.
   4. D. The cost of the cardboard.
5. What's the surface area of a cube with sides of 2 cm?
   1. A. 4 cm²
   2. B. 8 cm²
   3. C. 24 cm²
   4. D. 36 cm²
6. You're covering a book with contact paper. Which measurement helps you determine how much paper you need?
   1. A. The book's weight.
   2. B. The book's volume.
   3. C. The book's surface area.
   4. D. The book's number of pages.
7. Why is understanding surface area important in real life?
   1. A. It helps you calculate the distance between two cities.
   2. B. It helps you estimate the amount of material needed for different tasks.
   3. C. It helps you determine the temperature outside.
   4. D. It helps you predict the weather.