Area Problems The area of a circle is increased by 22 sq cm when its radius is increased by 1 cm. Find the original radius of the circle. 3.2 cm 6 cm 3.5 cm 3 cm 3.2 cm 6 cm 3.5 cm 3 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let original radius be r.Then, according to the questions,? (r + 1)2 - ?r2 = 22? ? x [(r + 1)2 - r2] = 22? (22/7) x (r + 1 + r ) x (r + 1 - r) = 22? 2r + 1 = 7 ? 2r = 6 ? r = 6/2 = 3 cm
Area Problems A circle and a square have same area. The ratio of the side of the square and the radius of the circle is? ?? : 1 ? : 1 1 : ?? 1 : ? ?? : 1 ? : 1 1 : ?? 1 : ? ANSWER EXPLANATION DOWNLOAD EXAMIANS APP ? Area of square = Area of circle ? x2 = ?r2? x/r = ?? = ? ? : 1
Area Problems What is the diameter of the circle having 3 cm radius? 1.5 cm 12 cm 6 cm 8 cm 1.5 cm 12 cm 6 cm 8 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Radius = Diameter/2 ? Diameter = 2 x Radius = 2 x 3 = 6 cm
Area Problems The area of sector of a circle of radius 5 cm, formed by an arc of length 3.5 cm is? 35 sq.cms 8. 75 sq.cms 55 sq.cms 17.5 sq.cms 35 sq.cms 8. 75 sq.cms 55 sq.cms 17.5 sq.cms ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Area of sector = ( arc length x radius ) / 2 cm2= (3.5 x 5 ) / 2= 8.75 cm2
Area Problems If 88 m wire is required to fence a circular plot of land, then the area of the plot is? 616 m2 None of these 556 m2 526 m2 616 m2 None of these 556 m2 526 m2 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Circumference of circular plot= 88 m? 2 x (22/7) x r = 88? r = 88 x (7/22) x (1/2) = 14 m Now area = ?r2=( 22/7) x 14 x 14 m2= 616 m2
Area Problems Find the area of the trapezium, whose parallel sides are 12 cm and 10 cm, and distance between the parallel sides is 14 cm? 164 sq.com 121 sq.com 154 sq.com 186 sq.com 164 sq.com 121 sq.com 154 sq.com 186 sq.com ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Area of trapezium = 1/2 x (Sum of parallel sides) x (Distance between Parallel sides) = 1/2 x (12 + 10) x 14 = 22 x 14/2 = 22 x 7 = 154 sq. cm
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