Area Problems A wheel makes 1000 revolutions in covering a distance of 88 km. the diameter of the wheel is? 24 meters 40 meters 28 meters 14 meters 24 meters 40 meters 28 meters 14 meters ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Distance covered in one revolution = total distance travelled / total number of revolution. = ( 88 x 1000) / 1000 m = 88 mWe know that the distance covered in one revolution = circumference of the wheel.? ?d = 88? 22d / 7 = 88? d = 28 m
Area Problems The area of circle is 38.5 sq. cm. Its circumference is? 6.20 cm 22 cm 11 cm 121 cm 6.20 cm 22 cm 11 cm 121 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP ? ( 22 x r2) / 7 = 38.5? r2 =(38.5 x 7) /22? r = 3.5 cm? Circumference = 2 x (22/7) x 3.5 cm= 22 cm
Area Problems If the sides of a squares is increased by 25%, then the area of the squares will be increased by 50% 125% 56.25% 53.75% 50% 125% 56.25% 53.75% ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Required increment = 2a + [a2 / 100] %= 2 x 25 + [(252)/100)] %= 50 + (625/100)% = 56.25%
Area Problems The ratio of the radii of two circle is 1:3 the radio of their areas is? 1:6 1:3 None of these 1:9 1:6 1:3 None of these 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 The area of a right angled triangle is 10 sq cm. If its perpendicular is equal to 20 cm, find its base. 1 cm 3 cm 4 cm 2 cm 1 cm 3 cm 4 cm 2 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Given that, area = 10 sq cm, perpendicular = 20 cm and base = ? area = (base x Perpendicular) / 2 ? 10 = (base x 20) / 2 ? base = 1 cm
Area Problems The area of the largest circle that can be drawn inside a rectangle with sides 18cm by 14cm is 378 49 154 1078 378 49 154 1078 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP The diameter is equal to the shortest side of the rectangle. So radius= 14/2 = 7cm. Therefore, area of circle = (r)2 = (22/7) x 49 = 154 cm2
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