Area Problems What is the diameter of the circle having 3 cm radius? 1.5 cm 8 cm 6 cm 12 cm 1.5 cm 8 cm 6 cm 12 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Radius = Diameter/2 ? Diameter = 2 x Radius = 2 x 3 = 6 cm
Area Problems The perimeter of a rectangle having area equal to 144 cm 2 and sides in the ratio 4 : 9 is 64 cm 60 cm 56 cm 52 cm 64 cm 60 cm 56 cm 52 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let l = 4k and b = 9kArea of rectangle = l x b144 = 4k x 9k ? k2 = 144/36 ? k2 = 4? k = 2? l = 8 cm and b = 18 cmPerimeter of rectangle = 2(l + b)= 2(8 + 18)= 2 x 26= 52 cm
Area Problems A tank is 25m long 12m wide and 6m deep. The cost of plastering its walls and bottom at 75 paise per sq m is Rs. 458 Rs. 558 Rs. 258 Rs. 358 Rs. 458 Rs. 558 Rs. 258 Rs. 358 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Area to be plastered = 2 l + b × h + l × b = 2 25 + 12 × 6 + 25 × 12 = 744 s q . m Cost of plastering = 744 × 75 100 = R s . 558
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 21.6 cm 19.8 cm 13.2 cm 26.4 cm 21.6 cm 19.8 cm 13.2 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Arc length = 2?r (?° / 360°) = 2 x (22/7) x 21 x (72° / 360°) cm= 26.4 cm
Area Problems Three circles of radius 3.5cm are placed in such a way that each circle touches the other two. The area of the portion enclosed by the circles is 1.967 1.767 1.867 1.567 1.967 1.767 1.867 1.567 ANSWER DOWNLOAD EXAMIANS APP
Area Problems A circular disc of area 0.49 ? square meters, rolls down a length of 1.76 km. The number of revolutions it makes is? 4000 600 400 300 4000 600 400 300 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Area = ?r2 = 0.49? ? r = 0.7 mNumber of revolutions = total distance / circumference = (1.76 x 1000) / (2 x 22/7 x 0.7) = 400
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