Area Problems If the sides of a rectangle are increased by 5%, find the percentage increase in its diagonals. 4% 5% 9% 6% 4% 5% 9% 6% ANSWER EXPLANATION DOWNLOAD EXAMIANS APP According to the formula,Percentage increase in diagonals = 5%
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? 19.8 cm 21.6 cm 13.2 cm 26.4 cm 19.8 cm 21.6 cm 13.2 cm 26.4 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 A triangle with three equal sides has its area equal to 3?3 sq cm . Find its perimeter . 2?3 cm 6?3 cm 5?3 cm 7?3 cm 2?3 cm 6?3 cm 5?3 cm 7?3 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP According to the question,?3a2/4 = 3?3 [ side = a, and area = ?3a2/4] ? a2/4 = 3 ? a2 = 3 x 4 ? a = 2?3? Required perimeter = 3a =3 x 2?3 = 6?3 cm
Area Problems If the diagonals of a rhombus are 4.8 cm 1.4 cm, then what is the perimeter of the rhombus? 5 cm 10 cm 12 cm 20 cm 5 cm 10 cm 12 cm 20 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Perimeter of rhombus= 2 ? d12 + d22 = 2 ?(4.8)2 + (1.4)2= 2 ?23.04 + 1.96 = 2 ?25 = 2 x 5 = 10 cm
Area Problems The area of a trapezium is 384 sq.cm. If its parallel sides in ratio 3 : 5 and the perpendicular distance between them be 12 cm. The smaller of parallel sides is? 16 cm 40 cm 24 cm 32 cm 16 cm 40 cm 24 cm 32 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the parallel sides be 3a and 5a.So Area of trapezium = 1/2 x sum of parallel side x perpendicular distance between them.? 1/2 (3a +5a) x 12 = 384? 8a = 64? a =8? Smaller side = 3x = 3 x 8 = 24 cm.
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
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