Mensuration (Railway Maths) (Part – VIII)

Total Questions: 50

41. Four circles of radius r cm are placed such a way that their centres form a square. Find the ratio of the area of the square (formed by the centres of the circles) to the area of the rhombus (formed by the touching points of the circles). [RRB NTPC 14/03/2021 (Evening) ]

Correct Answer: (d) 2 : 1
Solution:

42. A circle of radius 8 cm circumscribed a square. The length of the side of the square is: [RRB NTPC 15/03/2021 (Morning)]

Correct Answer: (c) 8√2 cm
Solution:

43. Find the area of a triangle whose sides are 5 cm, 7 cm and 11 cm. [RRB NTPC 15/03/2021 (Morning)]

Correct Answer: (b) 12.97 cm²
Solution:

44. A square park is surrounded by a path of uniform width 1.5 m all around it. The area of the path is 225 m². Find the perimeter of the park. [RRB NTPC 15/03/2021 (Morning)]

Correct Answer: (c) 144 m
Solution:

45. If the perimeter and area of a square are numerically equal then the side of the square is: [RRB NTPC 15/03/2021 (Evening)]

Correct Answer: (a) 4 units
Solution:

Perimeter and area are numerically equal,
4a = a² ⇒ a = 4 unit

46. Identical square slabs are used to pave the floor of a room 4.5 m long and 1.5 m in broad. Find the minimum number of such slabs that will be needed to pave the floor. [RRB NTPC 19/03/2021 (Morning)]

Correct Answer: (b) 3
Solution:

47. The hypotenuse of a right isosceles triangle is 28√2 cm. Find the area of the triangle. [RRB NTPC 19/03/2021 (Morning)]

Correct Answer: (c) 392 cm²
Solution:

48. The radius of a sphere r is equal to the radius of the base of a right circular cone. The total volume of the two shapes is (7/3)πr³. If 'h' is the height of the cone, find h/r. [RRB NTPC 19/03/2021 (Morning) ]

Correct Answer: (a) 3
Solution:

49. The difference between the circumference and the radius of the circle is 37 cm. The area of the circle is: [RRB NTPC 19/03/2021 (Evening) ]

Correct Answer: (b) 154 cm²
Solution:

50. If an equilateral triangle has an altitude of length 12√5 cm, then the difference between the areas of the circumscribed circle and the inscribed circle is: [RRB NTPC 19/03/2021 (Evening)]

Correct Answer: (d) 240π cm²
Solution: