Area Problems The base of a parallelogram is twice its height. If the area of the parallelogram is 338 sq.cm. Find its height? 16 cm 13 cm 14 cm 12 cm 16 cm 13 cm 14 cm 12 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let height =x Then, base =2x 2x * x = 338 =>x=13
Area Problems In a triangle ABC, BC = 5 cm AC = 12 cm and AB = 13 cm. The length of a altitude drawn from B on AC is? 7 cm 4 cm 5 cm 6 cm 7 cm 4 cm 5 cm 6 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP ? s= (13 + 5 + 12) / 2 cm = 15cms-a = 2 cm, s-b = 10 cm and s-c = 3 cm ? Area = ? (15 x 2 x 10 x 3 ) cm2= 30 cm2? (12 x h) / 2 = 30 ? h = 5 cm
Area Problems The ratio of the corresponding sides of two similar triangles is 3 : 4, The ratio of their areas is? ? 3: 2 9 : 16 4 : 3 3 : 4 ? 3: 2 9 : 16 4 : 3 3 : 4 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 the sides of a rectangle are increased by 5%, find the percentage increase in its diagonals. 4% 6% 5% 9% 4% 6% 5% 9% ANSWER EXPLANATION DOWNLOAD EXAMIANS APP According to the formula,Percentage increase in diagonals = 5%
Area Problems The cross section of a canal is a trapezium in shape . If the canal is a trapezium in shape. If the canal is 10 meters wide at the top and 6 meters wide at bottom and the area of cross section is 640 sq. meters The depth of canal is? 160 meters 80 meters 40 meters 384 meters 160 meters 80 meters 40 meters 384 meters ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Cross section area = 1/2 x ( a + b ) x d where a and b are the parallel sides, d is the perpendicular distance between them.? 1/2 x ( a + b ) x d = 640? d = (640 x 2) / 16 = 80m
Area Problems The ratio of the radii of two circle is 1:3 the radio of their areas is? None of these 1:9 1:6 1:3 None of these 1:9 1:6 1:3 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
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