Geometry (Railway Maths) (Part – I)

Total Questions: 50

41. In the given diagram, if <BAC = 30°, <ABC = 50° and <CDE = 25°, then <AED is equal to: [NTPC CBT - I 09/01/2021 (Evening) ]

Correct Answer: (a) 105°
Solution:

42. a,b,c are the sides of a right triangle with c as hypotenuse. The radius r of the circle which touches the three sides of the triangle is: [NTPC CBT - I 10/01/2021 (Evening) ]

Correct Answer: (b)
Solution:

43. If the radii of two circles are 4.5 cm and 3.5 cm, and the length of the transverse common tangent is 6 cm, then the distance between the two centers will be: [NTPC CBT-I 12/01/2021 (Morning)]

Correct Answer: (b) 10 cm
Solution:

44. The sides of a parallelogram are 3x + 2 and 5x + 4. It has a perimeter of 44 cm and an area of 64 cm². The value of the acute angle between its sides in degrees is: [NTPC CBT-I 13/01/2021 (Morning)]

Correct Answer: (a) between 30° and 60°
Solution:

exterior angle of the octagon = 180° - 135° = 45°

45. If a tangent to a circle from a point P meets the circle at A with AP = 15 cm. Given that the radius of the circle is 8 cm, find the distance of P from the centre of the circle. [NTPC CBT-I 21/01/2021 (Evening)]

Correct Answer: (b) 17 cm
Solution:

46. A square is inscribed in a circle which is inscribed in an equilateral triangle. If one side of a triangle is x, then the area of the square. [NTPC CBT - I 01/02/2021 (Evening) ]

Correct Answer: (d)
Solution:

47. In a circle, two chords of length x and y subtend the angles of 60° and 90° at the center respectively. Which of the following is correct in this scenario? [NTPC CBT-I 02/02/2021 (Evening)]

Correct Answer: (a) y = √2x
Solution:

48. What is the area of the largest square that is inscribed in a semicircle of radius 10 cm? [NTPC CBT-I 03/02/2021 (Evening)]

Correct Answer: (c) 80 cm²
Solution:

49. The difference between the interior and exterior angles at a vertex of a regular polygon is 140⁰. The number of sides of the polygon is: [NTPC CBT - I 08/02/2021 (Morning) ]

Correct Answer: (b) 18
Solution:

50. The angle formed by the pages of a fully open book, with just few pages, it theoretically: [NTPC CBT - I 09/02/2021 (Morning) ]

Correct Answer: (b) Straight angle
Solution:

The angle formed by the pages of a fully open book, with just a few pages, is theoretically a straight angle. The angle formed by the pages of an open book is an obtuse angle.