1. Mailey mother brought her a pet hamster. She is keeping Montey, the hamster, in a box with a length of 8.3 in.,a width of 6in.,and a height of 5,25in. Mailey plans on covering Montey's box with contact paper. How many square inches of contact paper is needed to completely cover the box?
2. A, Max is making a cylindrical bird feeder out of flexible plastic. He will need to leave only the bottom of the cylinder open. The bird feeder will be 18.5 inches tall, and have a radius of 3.5 inches. How many full inches of flexible plastic doses max née do construct the bird feeder?
B. If the flexible plastic cost $0.12, how much money will max spend to construct the bird feeder?
3. PJ collected rain water Ina small barrel that was 3.5 feet tall and had a diameter of 2 feet. At the end of the week, the water levels was 6 inches from the top of the barrel. About how many cubic of rain water were in the barrel? (12 inches=1 foot)
Which of these problems don't you understand?
All of them. These were the only 3 question that I did not get on my homework packet.
1.
2(8.3 * 6) + 2(8.3 * 5.25) + 2(6 * 5.25) = _______ sq. in.
2. A http://www.google.com/#q=surface+area+of+a+cylinder
2. B Multiply the surface area by $0.12
3.
https://www.google.com/#q=volume+of+a+cylinder
I still don't get #3
And do I have to find the lateral surface area of the cylinder on number 2 or the total surface area
1. To find the total surface area of the box, we need to calculate the area of each of its six sides and then sum them up. The box has a length of 8.3 inches, a width of 6 inches, and a height of 5.25 inches.
- The top and bottom sides have the same dimensions, so we can calculate their area by multiplying the length by the width: 8.3 inches * 6 inches = 49.8 square inches each.
- The two smaller sides have dimensions of 5.25 inches (height) by 8.3 inches (length), so their area is: 5.25 inches * 8.3 inches = 43.575 square inches each.
- The two longer sides have dimensions of 5.25 inches (height) by 6 inches (width), so their area is: 5.25 inches * 6 inches = 31.5 square inches each.
To find the total surface area, we add up the areas of all six sides: 49.8 + 49.8 + 43.575 + 43.575 + 31.5 + 31.5 = 249.75 square inches.
Therefore, you would need 249.75 square inches of contact paper to completely cover the box.
2a. To find the full length of flexible plastic needed to construct the cylinder-shaped bird feeder, we need to calculate the surface area of the side of the cylinder. Since the bottom is left open, we only need to consider the curved part of the cylinder.
- The surface area of the side of a cylinder can be calculated using the formula: 2 * pi * radius * height, where "pi" is a mathematical constant approximately equal to 3.14159, the radius is 3.5 inches, and the height is 18.5 inches.
Plugging in the values, we get: 2 * 3.14159 * 3.5 inches * 18.5 inches = 407.0795 square inches.
Therefore, Max would need approximately 407 square inches of flexible plastic to construct the bird feeder.
2b. If the flexible plastic costs $0.12 per square inch, we can calculate the total cost by multiplying the cost per square inch by the total area needed.
Cost = $0.12/square inch * 407 square inches = $48.84.
Therefore, Max would spend approximately $48.84 to construct the bird feeder.
3. To find the volume of the rainwater in the barrel, we need to calculate the volume of a cylinder. The barrel has a height of 3.5 feet and a diameter of 2 feet.
- The formula to calculate the volume of a cylinder is: pi * radius^2 * height, where "pi" is a mathematical constant approximately equal to 3.14159, the radius is half the diameter, and the height is 3.5 feet.
First, we need to convert the height to inches since the diameter was given in feet and inches: 3.5 feet * 12 inches/foot = 42 inches.
Next, we need to calculate the radius using half of the diameter: 2 feet / 2 = 1 foot = 12 inches.
Now we can calculate the volume: 3.14159 * (12 inches/2)^2 * 42 inches = 2,956.46944 cubic inches.
Since there are 12 inches in a foot, we divide the volume by 12^3 to convert cubic inches to cubic feet: 2,956.46944 cubic inches / (12 inches/foot)^3 = 1.70653 cubic feet.
Therefore, there are approximately 1.71 cubic feet of rainwater in the barrel.