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❗❗100 POINTS FOR CORRECT ANSWER AND EXPLANATION❗❗~math question~
thanks)​

❗❗100 POINTS FOR CORRECT ANSWER AND EXPLANATION❗❗~math question~ thanks)​-example-1
User Nazra
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1 Answer

19 votes
19 votes

Answer:

k = 110

Explanation:

You want the integer multiple of pi that is the area of 300° of a donut with inner radius 8 cm and outer radius of 14 cm.

Area of a circle

The area of a circle is given by the formula ...

A = πr²

Then the area of the outer circle is ...

A = π(14 cm)² = 196π cm²

The area of the inner circle is ...

A = π(8 cm)² = 64π cm²

Donut area

The area of the whole donut is the difference of these areas:

whole donut area = (196 -64)π cm² = 132π cm²

Shaded area

The shaded area of the figure represents 300° of the 360° full donut. The area is proportional to the central angle, so the shaded area is ...

shaded area = (300°/360°)×whole donut area

shaded area = 5/6 × 132π cm² = 110π cm²

Comparing this to the expression kπ cm², we see that ...

k = 110

User Niclas Nilsson
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