Area Problems The sides of a triangular board are 13 meters, 14 meters and 15 meters. The cost of paining it at the rate of Rs. 8.75 per m 2 is? Rs. 722.50 Rs. 730.80 Rs. 688.80 Rs. 735 Rs. 722.50 Rs. 730.80 Rs. 688.80 Rs. 735 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP s = (13 + 14 + 15 ) / 2 = 21, s-a = 8 , s-b = 7, s-c= 6? Area to be painted = ? [s(s-a) (s-b) (s-c)]=? [21 x 8 x 7 x 6] m2= 84 m2? Cost of painting = Rs. (84 x 8.75) = Rs. 735
Area Problems What is the area of a square having perimeter 68 cm? 361 sq cm 284 sq cm 289 sq cm 269 sq cm 361 sq cm 284 sq cm 289 sq cm 269 sq cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP According to the question,4a = 68 [ where a = side]?a = 68/4 = 17 cm? Required area = a2= (17)2 = 289 sq cm
Area Problems A man walked diagonally across a square lot. Approximately, what was the percent saved by not walking along the edges? 20 30 33 24 20 30 33 24 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the side of the square(ABCD) be x metres. Then, AB + BC = 2x metres. AC = √2x = (1.41x) m. Saving on 2x metres = (0.59x) m. Saving % = ❨ 0.59x x 100 ❩% = 30%
Area Problems If the ratio of the area of two square is 9 : 1 the ratio of their perimeters is? 9:1 3:1 3:4 1:3 9:1 3:1 3:4 1:3 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the area of square be (9x)2 m2 and (x2) m2Then, their sides are (3x) m and x metres respectively? Ratio of their perimeters = 12x / 4x=3:1
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? 13.2 cm 26.4 cm 21.6 cm 19.8 cm 13.2 cm 26.4 cm 21.6 cm 19.8 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 If the circumference of a circle is the 352 meters, then its area in m square is? 5986 6589 9856 8956 5986 6589 9856 8956 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP circumference = 2?r = 2 x (22 / 7) x r = 352? r = (352 x 7) / (22 x 2) =56 cmNow area = ?r2 = (22 / 7) x 56 x 56 m2= 9856 m2
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