1). The length and breadth of a rectangle is 136 cm. and 102 cm respectively, its area is
View Answer Correct Answer: 1.39 \( \Large m^{2} \) \( \Large A = l \times b \) => \( \Large 1.36m \times 1.02m = 1.39 m^{2} \)
 
2). The area of a rhombus is 120 \( \Large cm^{2} \). If one of its diagonals is of length 10 cm, then length of one of its sides is
View Answer Correct Answer: 13 cm Area of a rhombus = = \( \Large \frac{1}{2} \times Product\ of\ its\ diagonals. \)
 
3). The area of a rectangular ground is 12500 \( \Large m^{2} \). If its length is 125 m, then its perimeter is
View Answer Correct Answer: 450 m Area of rectangle (A) = \( \Large l \times b \) \( \Large 12500 = 125 \times b \) Therefore, \( \Large b = \frac{12500}{125} \) Therefore, b = 100 m Now perimetre of rectangle = \( \Large 2 \left(l+b\right) \) = \( \Large 2 \left(125+100\right) \) = 450 m
 
4). The length and the breadth of a rectangle are 120 meters and 50 meters respectively, then length of the diagonal of the rectangle is
View Answer Correct Answer: 130 m Length of diagonal of the rectangle = \( \Large \sqrt{l^{2}+b^{2}} \) = \( \Large \sqrt{ \left(120\right)^{2}+ \left(50\right)^{2} } =\ 130\ m \)
 
5). Three cubes whose edges measure 3 cm, 4cm and 5cm respectively are melted to form a new cube. The surface area of the new cube is
View Answer Correct Answer: 216 \( \Large cm^{2} \) If a is side of the new cube, then \( \Large a^{3}= \left(3^{3}+4^{3}+5^{3}\right) \) \( \Large = 27 + 64 + 125 \) = \( \Large 216 = 6^{3} \) Therefore, a = 6 cm Surface area of the new cube =\( \Large 6a^{2} = 6 \times 6^{2} \) =\( \Large 216\ cm^{2} \)
 
6). The length and breadth of a hall are 60m and 50m respectively. Length of a 2 meter wide carpet to cover the whole floor of the room is
View Answer Correct Answer: 1500 m \( \Large 2 \times l = 60 \times 50 \) Therefore, Required length, l = 1500 m
 
7). The areas of a rectangle and a square are equal. The side of the square is 5 cm and the smaller side of the rectangle is half that of the square. The length of other side of the rectangle would be
View Answer Correct Answer: 10 cm Side of square = 5 cm
 
8). A rectangular hall 108 meters long is paved with 7128 tiles each measuring 5 \( \Large dm^{2} \), then Width of the plot is
View Answer Correct Answer: 3.3 m \( \Large 108 \times b = 7128 \times 5 \times \left(\frac{1}{10}m\right)^{2} \) \( \Large \left(\because\ 1 m^{2} = 100\ dm^{2}\right) \) Therefore, Width of plot, b = 3.3 m
 
9). The perimeter of a square is 12 cm and that of another is 16 cm. The side of a square whose area is equal to the sum of the areas of the above two squares would be
View Answer Correct Answer: 5 cm Perimeter of first square = 12 cm.
 
10). If length of a square is doubled its area will increase
View Answer Correct Answer: four times Let the length of one square be 'a' cm and length of another square be '2a' cm. Therefore, Increased Area = \( \Large \left(2a\right)^{2} \left(a\right)^{2}= 3a^{2} \)

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