To start, the question is asking for surface area of a cylinder, meaning you will have to use this formula to find it: A=2πrh+2πr^2.
Since you already know that the diameter of the plastic cylinder is 4 marbles long, and each marble is 2 cm in diameter, you would multiply 4 and 2 to get that your diameter is 8 cm. However, since the surface area of a cylinder formula uses radius, you would simply divide 8 by 2 to get that the radius of the cylinder is 4 cm.
Now, since you already know that the height of the cylinder is equal to 10 marbles, multiply the amount of marbles by 2 to get that the height of the cylinder is 20 cm.
Now that you know the height and the diameter of the cylinder, plug the values into the formula: A=2π(4)(20)+2π(4)^2.
Assuming that pi is 3.14, simplify the equation as according to PEMDAS and you get that the area of plastic needed to make one cylinder is 602.88 cm squared
Answer:
Blue Rectangle: <u>135 mm²</u>
Blue Triangle: <u>45 mm²</u>
<em>Not sure if you need this but the </em>Total Square: <u>225 mm²</u>
Step-by-step explanation:
Area of a rectangle: <u>length x width</u>
Area of a triangle:
<u> x base x height</u>
First find the area of the blue rectangle.
Length = 15 mm
Width = 9 mm
Area = 135 mm²
Now find the area of the blue triangle:
Base = 6 mm (because the bottom is 15 total and you subtract the 9)
Height = 15 mm
Area = 45 mm²
Hope it helps!
The value of x is
and 
Step-by-step explanation:
The equation is 
Subtracting by
on both sides,

Taking LCM,

Multiplying by 3x on both sides,

Dividing by (-) on both sides,

Using quadratic formula, we can solve for x.

Taking out common term 2, we get,

Thus, the value of x is
and 
Answer:
45%
Step-by-step explanation:
40 * .45 = 18
40-18 = 22