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Perimeter = 210cm
Calculate the radius of the sector
Angle is 30

User Arnpry
by
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1 Answer

1 vote

Answer:

Explanation:

Let the length of the arc of the sector which subtend angle of 30°,2πrx°/360 where x°=30°, this can also be written as πrx°/180 .Perimeter of a sector

2r+ arc length.

Now let the arc length = 22/7 x r x 30/180; this gives, 11r/21cm. Therefore the perimeter = r + r + 11r/21 = 210.

Solving for r in the equation

2r + 11r/21 = 210, multiply through by 21, we now have 42r + 11r = 4410

53r = 4410; divide through by 53, r = 83.2cm. Therefore the length of the arc = 11r/21, 11 x 83.2/21 = 43.6cm.

Check: 2r + 11r/21, 2 x 83.2 + 43.6 = 210cm.

Therefore the radius of the sector

r = 83.2cm.

User Markwilde
by
5.4k points