Area Problems The area of rectangle whose length is 5 more than twice its width is 75 sq units. What is the perimeter of the rectangle? 20 unit 24 unit 30 unit 40 unit 20 unit 24 unit 30 unit 40 unit ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the width of the rectangle = k units? Length = (2k + 5) units.According to the question,Area = k(2k + 5)? 75 = 2k2 + 5k? 2k2 + 5k - 75 = 0 ? 2k2 + 15k - 10k - 75 = 0 ? k(2k + 15) - 5(2k + 15) = 0 ? (2k + 15) (k - 5) = 0 ? k = 5 and -15/2Width cannot be negative. ? Width = 5 units? Length = 2x + 5 = 2 x 5 + 5 = 15 unit? perimeter of the rectangle = 2(15 + 5) = 40 units
Area Problems The area of a trapezium is 384 sq.cm 2. If its parallel sides are in ratio 3 : 5 and the perpendicular distance between them be 12 cm, The smaller of parallel sides is? 20 cm 36 cm 24 cm 30 cm 20 cm 36 cm 24 cm 30 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the sides of trapezium be 5k and 3k, respectively According to the question, (1/2) x [(5k + 3k) x 12] = 384? 8k = (384 x 2)/12 = 64 ? k = 64/8 = 8 cmLength of smaller of the parallel sides = 8 x 3 = 24 cm
Area Problems The area of the sector of a circle, whose radius is 12 meters and whose angle at the centre is 42, is? 79.2 sq. meters 26.4 sq. meters 39.6 sq. meters 52.8 sq. meters 79.2 sq. meters 26.4 sq. meters 39.6 sq. meters 52.8 sq. meters ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Area of the sector = [(22/7) x 12 x 12] x [42°/360°] m2 = 52.8 m2
Area Problems The area of an equilateral triangle is ? 243 /4 sq cm. Find the length of its side. 3?3 cm 3 cm 9 cm ?3 cm 3?3 cm 3 cm 9 cm ?3 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP According to the question,area = ?3a2/4 = ?243 /4? a2 = ?81 x 3/?3 ? a = ?9 = 3 cm
Area Problems The ratio between the lenght and the breadth of a rectangle is 2 : 1. If breadth is 5 cm less than the length, what will be the parimeter of the rectangle? 25 cm 40 cm 35 cm 30 cm 25 cm 40 cm 35 cm 30 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let length = 2x and breadth = xAccording to the question, 2x - x = 5 ? x = 5? Required perimeter = 2(2x + x) = 6x= 30 cm
Area Problems One side of a rectangular field is 4 meter and its diagonal is 5 meter. The area of the field is? 12 m2 20 m 2 15 m2 4?5 m2 12 m2 20 m 2 15 m2 4?5 m2 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Other side = ?5 2 - 42 = ? 9=3 mSo The area of the rectangular field = 4 x 3 = 12 m2
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