Area Problems The ratio of the radii of two circle is 1:3 the radio of their areas is? 1:9 None of these 1:6 1:3 1:9 None of these 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
Area Problems Angles of a quadrilateral are in the ratio 3 : 4 : 5 : 8. The smallest angle is 40° 54° 36° 18° 40° 54° 36° 18° ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let First angle = 3kSecond angle = 4kThird angle = 5k and Fourth angle = 8kWe know 3k + 4k + 5k + 8k = 360°? 20k = 360° ? k = 18 °Measure of smallest angle = 3k =3 x 18 ° = 54 °
Area Problems The ratio between the lenght and the breadth of a rectangle is 2 : 1. If breadth is 5 cm less than the length, what will be the parimeter of the rectangle? 35 cm 30 cm 25 cm 40 cm 35 cm 30 cm 25 cm 40 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let length = 2x and breadth = xAccording to the question, 2x - x = 5 ? x = 5? Required perimeter = 2(2x + x) = 6x= 30 cm
Area Problems The area of a rectangle is 460 square metres. If the length is 15% more than the breadth, what is the breadth of the rectangular field? 30 m 50 m 20 m 40 m 30 m 50 m 20 m 40 m ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let breadth = x meters. Then, Length = 115x / 100 meters Given that, X × (115X / 100) = 460 => X = 20
Area Problems A wire can be bent in the form of a circle of radius 56cm. If it is bent in the form of a square, then its area will be 5544 8844 4444 7744 5544 8844 4444 7744 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP length of wire = 2 ?r = 2 x (22/7 ) x 56 = 352 cmside of the square = 352/4 = 88cmarea of the square = 88 x 88 = 7744sq cm
Area Problems The radius of a circle is so increased that its circumference increased by 5%. The area of the circle, then increases by 10.25% 12.5% 11.25% 10.5 % 10.25% 12.5% 11.25% 10.5 % ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Increase in circumference of circle = 5%? Increase in radius is also 5%.Now, increase in area of circle = 2a + (a2/100) %Where, a = increase in radius= 2 x 5 + (5 x 5)/100 % = 10.25%
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