Area Problems The sides of a triangular board are 13 meters, 14 meters and 15 meters. The cost of paining it at the rate of Rs. 8.75 per m 2 is? Rs. 688.80 Rs. 735 Rs. 722.50 Rs. 730.80 Rs. 688.80 Rs. 735 Rs. 722.50 Rs. 730.80 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP s = (13 + 14 + 15 ) / 2 = 21, s-a = 8 , s-b = 7, s-c= 6? Area to be painted = ? [s(s-a) (s-b) (s-c)]=? [21 x 8 x 7 x 6] m2= 84 m2? Cost of painting = Rs. (84 x 8.75) = Rs. 735
Area Problems A wheel make 4000 revolution in moving a distance of 44 km. Find the radius of the wheel. 28 m 1.75 m 25 m 27 m 28 m 1.75 m 25 m 27 m ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Distance covered in 1 revolution = (44 x 1000) / 4000 = 11 mAccording to the question, 2?r = 11 ? (44/7) x r = 11? r = (11 x 7) / 44 = 1.75 m
Area Problems A railing of 288 m is required for fencing a semi-circular park. Find the area of the park. (? = 22/7) 4928 m2 9865 m2 8956 m2 9856 m2 4928 m2 9865 m2 8956 m2 9856 m2 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the radius of the park be r, then?r + 2r = 288(? + 2)r = 288? [(22/7) + 2]r = 288? r = (288 x 7)/36 = 56 ? Area of the park = (1/2)?r2= (1/2) x (22/7) x 56 x 56= 4928
Area Problems The ratio of the corresponding sides of two similar triangles is 3 : 4, The ratio of their areas is? 4 : 3 3 : 4 9 : 16 ? 3: 2 4 : 3 3 : 4 9 : 16 ? 3: 2 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Ratio of similar triangle = Ratio of the square of corresponding sides = (3x)2 / (4x)2 = 9x2 / 16x2 = 9/16 = 9 : 16
Area Problems If a regular hexagon is inscribed in a circle of radius, r then its perimeter? 3r 12r 9r 6r 3r 12r 9r 6r ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Length of each side of hexagoan = radius of circle ? its perimeter = 6r
Area Problems The ratio of the area of the circumcircle and the incircle of a square is 1 : 2 1 : ?2 2 : 1 ?2 : 1 1 : 2 1 : ?2 2 : 1 ?2 : 1 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Ratio of the areas of the circumcircle and incircle of a square = [(Diagonal)2?] / [(Side)2?]= [(Side x ?2)2] / (Side)2 = 2/1 or 2 : 1
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