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Please answer this correctly

Please answer this correctly-example-1
User Luca Putzu
by
4.6k points

2 Answers

4 votes

Answer:

879.20 km²

Explanation:

Shaded area= Area of whole circle- area of white circle

Area of circle= πr²

Radius of whole circle= 10+18/2= 19 km

Area of whole circle= 3.14*(19 km)²= 1133.54 km²

Are of white circle= 3.14*(9 km)²= 254.34 km²

Shaded area= 1133.54 km²- 254.34 km²= 879.20 km²

Answer is 879.20 km²

User Fattire
by
4.5k points
4 votes

Answer: 879.20 km²

Explanation:

The diameter of the big circle is 2(10) + 18 = 38

divide the diameter by 2 to get the radius (r) = 19

Area (A) = π·r²

= π(19)²

= 361π

The diameter of the small circle is 18

divide the diameter by 2 to get the radius (r) = 9

Area (A) = π·r²

= π(9)²

= 81π

The area of the shaded region is the difference between the big circle and the small circle.


Area_(shaded)=A_(big)-A_(small)

= 361π - 81π

= 280π

= 280(3.14)

= 879.20

User William Ardila
by
4.3k points