PLZ HELP
1 answer:
Answer:
80πcm²
Please see the attached file for your reference
Step-by-step explanation:
This problem bothers on the mensuration of solid shapes, a cone
The total surface area of cone is the sum of the curved surface area and the base surface area
Curved surface area = πrl
Base area = πr²
From the figure
The surface area to be painted is
Base area - area of hole
Given diameter of base = 12cm
Radius of base = 12/2= 6cm
Area of base = π(6²)
Area of base = 36πcm²
Area of hole =πr²
Given radius of hole = 4cm
Area =π(4²)
Area = 16πcm²
Hence area to be painted at the base is 36πcm²- 16πcm²
Area to be painted at base 20πcm²
For the curved surface area
Area = πrl
Sine the base radius is 6cm
Given height h= 8cm
We need to find the slant height l
Since the slant height the height and the radius of a cone forms a right triangle
Applying Pythagoras theorem
l= √r²+h²
l= √6²+8²
l=√36+64
l=√100
l= 10cm
We can now solve for the curved surface area
A=πrl
A= π*6*10
A= 60πcm²
Hence the total surface area to be painted is 60πcm² +20πcm²
80πcm²
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Answer:
F. 2 1/9
Step-by-step explanation:
Step 1: Substitute q
When you plug in <em>n</em> = 1, 2, 3:
n(1) = 3
n(2) = 2.11111
n(3) = 2.3333
So our answer is F.