Area Problems Find the area of a rectangle having 15m length and 8m breadth. 120 sq m 115 sq m 111 sq m 125 sq m 120 sq m 115 sq m 111 sq m 125 sq m ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Required area = Length x Breadth= 15 x 8 = 120 sq m
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? 21.6 cm 26.4 cm 19.8 cm 13.2 cm 21.6 cm 26.4 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 The length of a rectangle is double while its breadth is halved. What is the percentage change in area? None of these 75 No change 50 None of these 75 No change 50 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let length = l and breadth = bThen, area = lb New length = 2lAnd new breadth = b/2 ? New area = ( 2l ) x (b/2) = lbSo, there is no change in area .
Area Problems A tank is 25 m long, 12 m wide and 6 m deep. The cost of plastering its walls and bottom at 75 paise per sq. m, is: Rs. 558 Rs. 458 Rs. 568 Rs. 456 Rs. 558 Rs. 458 Rs. 568 Rs. 456 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Area to be plastered = [2(l + b) x h] + (l x b) = {[2(25 + 12) x 6] + (25 x 12)} m2 = (444 + 300) m2 = 744 m2. ∴ Cost of plastering = Rs. ❨ 744 x 75 ❩ = Rs. 558
Area Problems The length and breadth of a playground are 36 m and 21 m respectively. Flagstaffs are required to be fixed on all along the boundary at a distance of 3 m apart. The number of flagstaffs will be? 38 40 37 39 38 40 37 39 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Perimeter = 2 x (36 + 21 ) m = 144 m ? Number of flagstaffs = 144 / 3 = 38
Area Problems What is the least number of squares tiles required to pave the floor of a room 15 m 17 cm long and 9 m 2 cm broad? 840 820 814 844 840 820 814 844 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Length of largest tile = H.C.F. of 1517 cm and 902 cm = 41 cm. Area of each tile = (41 x 41) cm2. ∴ Required number of tiles = ❨ 1517 x 902 ❩ = 814
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