Area Problems The length of a rectangular field is 100 m and its breadth is 40 m. What will be the area of the field? (4 x 103) sq m (4 x 10) sq m (4 x 104) sq m (4 x 102) sq m (4 x 103) sq m (4 x 10) sq m (4 x 104) sq m (4 x 102) sq m ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Required area = Length x Breadth= 100 x 40 = 4000 sq m= 4 x 103 sq m
Area Problems The area of the sector of a circle, whose radius is 12 meters and whose angle at the centre is 42, is? 39.6 sq. meters 52.8 sq. meters 79.2 sq. meters 26.4 sq. meters 39.6 sq. meters 52.8 sq. meters 79.2 sq. meters 26.4 sq. meters ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Area of the sector = [(22/7) x 12 x 12] x [42°/360°] m2 = 52.8 m2
Area Problems If the sides of a rectangle are increased by 5%, find the percentage increase in its diagonals. 9% 5% 4% 6% 9% 5% 4% 6% ANSWER EXPLANATION DOWNLOAD EXAMIANS APP According to the formula,Percentage increase in diagonals = 5%
Area Problems The area of circle inscribed in an equilateral triangle is 462 cm . The perimeter of the triangle is? 72.6 cms 168 cms 42 ? 3 cms 126 cms 72.6 cms 168 cms 42 ? 3 cms 126 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 The ratio of the radii of two circle is 1:3 the radio of their areas is? None of these 1:6 1:3 1:9 None of these 1:6 1:3 1:9 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP The Radio of areas = area of first circle : area of 2nd circle= ?r2 / ?(3r)2= ?r2/ 9 ?r2= 1/9 = 1: 9
Area Problems In a circle of radius 21 cm an arc subtends an angle of 72° at the centre. The length of the arc is? 26.4 cm 13.2 cm 21.6 cm 19.8 cm 26.4 cm 13.2 cm 21.6 cm 19.8 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Arc length = 2?r (?° / 360°) = 2 x (22/7) x 21 x (72° / 360°) cm= 26.4 cm