PQRS is a diameter of a circle of radius 6cm. The lengths PQ, QR and.RS are equal- Semicircles are drawn on PQ and QS as diameters is shown
Answers
Answered by
4
ps = 12 cm
⇒pq = qr =rs
∴ pq =qr =rs = 1/3 x ps = 1/3 x 12 = 4 cm.
qs = 2 pq
qs = 2 x 4 = 8 cm
∴ area of shaded region = area of semicircle with ps as diameter + area of semicircle with pq as diameter – area of semicircle with qs as diameter
= 1/2 [ 3.14 x 6² + 3.14 x 2² - 3.14 x 4² ]
= 1/2 [ 3.14 x 36 + 3.14 x 4 – 3.14 x 16 ]
= 1/2[ 3.14 ( 36 + 4 – 16)]
= 1/2 ( 3.14 x 24 ) = 1/2 x 75.36
∴ area of shaded region = 37.68 cm²
Perimeter of shaded region=12*22/7 =264/7
⇒pq = qr =rs
∴ pq =qr =rs = 1/3 x ps = 1/3 x 12 = 4 cm.
qs = 2 pq
qs = 2 x 4 = 8 cm
∴ area of shaded region = area of semicircle with ps as diameter + area of semicircle with pq as diameter – area of semicircle with qs as diameter
= 1/2 [ 3.14 x 6² + 3.14 x 2² - 3.14 x 4² ]
= 1/2 [ 3.14 x 36 + 3.14 x 4 – 3.14 x 16 ]
= 1/2[ 3.14 ( 36 + 4 – 16)]
= 1/2 ( 3.14 x 24 ) = 1/2 x 75.36
∴ area of shaded region = 37.68 cm²
Perimeter of shaded region=12*22/7 =264/7
Similar questions