Mensuration (Railway Maths) (Part – VII)

Total Questions: 50

21. A path around the inner side of a rectangular park measuring 37 m × 30 m occupies 570 m². What is the width of the path? [RRB NTPC 01/02/2021 (Evening)]

Correct Answer: (c) 5 m
Solution:

22. A cube of volume 324 cm³ is molded into a cuboid whose length, width and height are in the ratio 3 : 2 : 2. Find the length of the cuboid. [RRB NTPC 02/02/2021 (Evening)]

Correct Answer: (c) 9 cm
Solution:

23. The ratio of an interior angle to the exterior angle of a regular polygon is 4 : 1. The number of sides of the polygon is: [RRB NTPC 03/02/2021 (Morning)]

Correct Answer: (b) 10
Solution:

24. If the ratio of the heights of two cones is 1 : 4 and the diameters are in the ratio 4 : 5, then what is the ratio of their volumes? [RRB NTPC 03/02/2021 (Evening)]

Correct Answer: (a) 4 : 25
Solution:

Ratio of the heights of two cones is 1 : 4
Ratio of diameter = 4 : 5
Ratio of radius = 4 : 5
Ratio of volumes = 4² × 1 : 5² × 4 = 4 : 25

25. If the length, breadth and height of a room are 20 m, 25 m and 35 m respectively, then what will be the total surface area of the four walls of the room? [RRB NTPC 04/02/2021 (Morning)]

Correct Answer: (c) 3150 m²
Solution:

L = 20 m , B = 25 m and H = 35 m
Total surface area of the Room
= 2 (L + B) H = 2(45) × 35 = 3150 m²

26. In a right circular cylinder, the ratio of the curved surface area to the total surface area is 5 : 9. Find the ratio of the height of the cylinder to the radius of the cylinder. [RRB NTPC 04/02/2021 (Morning) ]

Correct Answer: (b) 5 : 4
Solution:

27. Flooring of a room 12 m long and 8 m wide is to be designed by squares of the maximum possible area. Find the number of square designs required. [RRB NTPC 04/02/2021 (Evening) ]

Correct Answer: (b) 6
Solution:

28. In a polygon, the sum of the interior angles is triple the sum of the exterior angles. The number of sides is: [RRB NTPC 04/02/2021 (Evening) ]

Correct Answer: (a) 8
Solution:

29. Find the answer of given question? [RRB NTPC 05/02/2021 (Morning) ]

Correct Answer: (b) 60 cm
Solution:

30. The area of a rectangle is 1287 cm² and length and breadth are in the ratio 13 : 11 respectively. What is the perimeter? [RRB NTPC 08/02/2021 (Morning) ]

Correct Answer: (b) 144 cm
Solution: