Mensuration (Railway Maths) (Part – VI)

Total Questions: 50

31. If the radius of a sphere is 21 cm, what will be its volume? [RRB NTPC 18/01/2021 (Evening)]

Correct Answer: (d) 38808 cm³
Solution:

32. What will be the area of a parallelogram with base 44 cm and height 22 cm? [RRB NTPC 18/01/2021 (Evening)]

Correct Answer: (a) 968 cm²
Solution:

The area of a parallelogram with base 44 cm and height 22 cm
= base × height = 44 × 22 = 968 cm²

33. The area of a circular park is 1386 m². If a path of the width 7 m is laid around and inside the park. Then the area of the path is. [RRB NTPC 19/01/2021 (Morning)]

Correct Answer: (b) 770 m²
Solution:

34. If the radii of two cylinders are in ratio 2 : 3 and their respective heights are in ratio 5 : 3 then what is the ratio of their volumes? [RRB NTPC 19/01/2021 (Evening)]

Correct Answer: (c) 20 : 27
Solution:

35. What will be the area of the ring-shaped region enclosed between two concentric circles of radii 14 cm and 7 cm? [RRB NTPC 20/01/2021 (Morning)]

Correct Answer: (c) 462 cm²
Solution:

36. The ratio of the area of a circle and that of an equilateral triangle, where the diameter of a circle is equal to the sides of the equilateral triangle is. [RRB NTPC 20/01/2021 (Evening)]

Correct Answer: (b) π : √3
Solution:

37. A photograph of bacteria enlarged 60000 times attains a length of 6 cm. The actual length of bacteria is: [RRB NTPC 20/01/2021 (Evening)]

Correct Answer: (b) 1/10000 cm
Solution:

Let the actual length of bacteria = x cm
A/Q, 60000x = 6 ⇒ x = 1/10000 cm

38. The ratio of the volumes of two cubes is 64 : 1331. What is the ratio of their total surface areas? [RRB NTPC 21/01/2021 (Morning)]

Correct Answer: (a) 16 : 121
Solution:

39. A sector of a circle has a radius of 18 cm and a central angle of 125°. What will be its approximate perimeter? (Use π = 22/7) [RRB NTPC 21/01/2021 (Morning)]

Correct Answer: (d) 75.3 cm
Solution:

40. The angle of elevation of ladder leaning against a wall is 45°. The foot of the ladder is 4√2 meters away from the wall. The length of the ladder is: [RRB NTPC 21/01/2021 (Morning)]

Correct Answer: (d) 8 m
Solution: