Area Problems In a triangle ABC, BC = 5 cm AC = 12 cm and AB = 13 cm. The length of a altitude drawn from B on AC is? 7 cm 6 cm 5 cm 4 cm 7 cm 6 cm 5 cm 4 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP ? s= (13 + 5 + 12) / 2 cm = 15cms-a = 2 cm, s-b = 10 cm and s-c = 3 cm ? Area = ? (15 x 2 x 10 x 3 ) cm2= 30 cm2? (12 x h) / 2 = 30 ? h = 5 cm
Area Problems If the base of a rectangular is increased by 10% and the area is unchanged , then the corresponding altitude must to be decreased by? 111/9 % 11% 91/11 % 10% 111/9 % 11% 91/11 % 10% ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let base = b and altitude = h Then, Area = b x h But New base = 110b / 100 = 11b / 10Let New altitude = HThen, Decrese = (h - 10h /11 )= h / 11? Required decrease per cent = (h/11) x (1 / h ) x 100 %= 91/11 %
Area Problems Square units 13 by 9 of an office area is 97 107 117 127 97 107 117 127 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Square units 13 by 9 of an office means office of length 13 units and breadth 9 units. Now its area is 13x 9 = 117 square units or units square.
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 If the circumference of a circle is the 352 meters, then its area in m square is? 5986 8956 6589 9856 5986 8956 6589 9856 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
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? 20 m 40 m 50 m 30 m 20 m 40 m 50 m 30 m ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let breadth = x meters. Then, Length = 115x / 100 meters Given that, X × (115X / 100) = 460 => X = 20
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