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3 years ago

A circle with radius 9 has a sector with a central angle of 120°.

Mathematics

1 answer:

Vitek1552 [10]3 years ago

8 0

120º is 1/3 of a complete revolution of 360º. So the area of this sector should be 1/3 the area of the complete circle.

A circle with radius 9 has area 9^2 π = 81π.

So the sector has area 81π/3.

Put another way: The area A of a circular sector and its central angle θ (in degrees) occur in the same ratio as the area of the entire circle with radius r according to

A / θ º = (π r ^2) / 360º

==> A = π/360 θ r ^2

In this case, r = 9 and θ = 120º, so

A = π/360 * 120 * 81 = 81π/3

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Answer:

Step-by-step explanation:

From the given information;

Numbers of posters that can be printed in an hour = no of impression/hour × no of plate utilized in each impression.

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If each plate costs $20 to make, then the total number of plate will equal to 40x

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At C'(x) = 0

$\dfrac{12500}{x^2} = 20$

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where; x = 25

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3 years ago

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3 years ago

What is the correct symbol?

Nadusha1986 [10]

Answer:

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Step 1: Solve the fraction

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