Area Problems The ratio of the corresponding sides of two similar triangles is 3 : 4, The ratio of their areas is? 9 : 16 3 : 4 4 : 3 ? 3: 2 9 : 16 3 : 4 4 : 3 ? 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 The perimeter of an isosceles triangle is 26 cm while equal sides together measure 20 cm. The third side and each of the equal sides are respectively. 6 cm and 10 cm 10 cm and 8 cm 8 cm and 9 cm 14 cm and 6 cm 6 cm and 10 cm 10 cm and 8 cm 8 cm and 9 cm 14 cm and 6 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the third side be x.According to the question,x + 20 = 26? x = 26 - 20 = 6 cm ? Each equal side = 20/2 = 10 cm
Area Problems A circular disc of area 0.49 ? square meters, rolls down a length of 1.76 km. The number of revolutions it makes is? 4000 400 300 600 4000 400 300 600 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Area = ?r2 = 0.49? ? r = 0.7 mNumber of revolutions = total distance / circumference = (1.76 x 1000) / (2 x 22/7 x 0.7) = 400
Area Problems The area of circle inscribed in an equilateral triangle is 462 cm . The perimeter of the triangle is? 126 cms 42 ? 3 cms 72.6 cms 168 cms 126 cms 42 ? 3 cms 72.6 cms 168 cms ANSWER EXPLANATION DOWNLOAD EXAMIANS APP ? 22/7 x r2 = 462? r2 = (462 x 7) /22 = 147? r = 7?3 cm ? Height of the triangle = 3r = 21?3 cmNow, ? a2 = a2/4 + (3r)2? 3a2/4 = (21?3)2? a2 = (1323 x 4)/3? a = 21x 2 = 42 cm? Perimeter = 3a = 3 x 42=126 cm
Area Problems A rectangular carpet has an area of 120 sq. m and a perimeter of 46 m . The length of its diagonal is? 15 m 17 m 16 m 20 m 15 m 17 m 16 m 20 m ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let length = a metres and breadth = b metres Then, 2(a+b)= 46 ? (a+b) =23 and ab =120 ? Diagonal = ?a2 + b2?(23)2-2 x 120?289 = 17 m
Area Problems Find the length of a rope by which a cow must be tethered in order that it may be able to graze an area of 9856 sq meters. 16m 14m 56m 76m 16m 14m 56m 76m ANSWER EXPLANATION DOWNLOAD EXAMIANS APP clearly the cow will graze a circular field of area 9856 sq m and radius equal to the length of the rope. Let the length of the rope be r mts then, r2 = 9856 r2 = (9856 × 7) / 22 = 3136 r = 56 m
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