Today i am solving the ncert class 10 chapter areas related to circles of exercise 12.3 question no. 12 . Please give me the best and easiest solution of this question ,find the simplest solution of this question i want to solve this tricky question easily. In Fig. 12.30, OACB is a quadrant of a circle with centre O and radius 3.5 cm. If OD = 2 cm, find the area of the (i) quadrant OACB, (ii) shaded region.

SonuNewbie

# In Fig. 12.30, OACB is a quadrant of a circle with centre O and radius 3.5 cm. If OD = 2 cm, find the area of the (i) quadrant OACB, (ii) shaded region. Q.12

Share

Radius of the quadrant = 3.5 cm = 7/2 cm

(i)Â Area of quadrant OACB = (Ï€R^{2})/4 cm^{2}= (22/7)Ã—(7/2)Ã—(7/2)/4 cm

^{2}= 77/8 cm

^{2}(ii)Â Area of triangle BOD = (Â½)Ã—(7/2)Ã—2 cm^{2}= 7/2 cm

^{2}Area of shaded region = Area of quadrant â€“ Area of triangle BOD

= (77/8)-(7/2) cm

^{2Â }= 49/8 cm^{2}= 6.125 cm

^{2}