RRB NTPC 2021 PYQs

Question 1

Which architect has designed the India Gate in New Delhi?

Accepted Answer

India Gate, a prominent war memorial in New Delhi, was designed by the renowned British architect Sir Edwin Lutyens. He also played a key role in designing much of New Delhi.

Question 2

15 male employees or 20 female employees of a company can complete a project in 26 days. How long will 30 male employees and 12 female employees together take to complete the project?

Accepted Answer

Equate work done by men and women: 15M = 20W, so 3M = 4W. Convert 30M + 12W to women-equivalent: 40W + 12W = 52W. If 20W take 26 days, then 52W take (20*26)/52 = 10 days.

Question 3

Where is the Sambhar Lake situated?

Accepted Answer

Sambhar Lake, India's largest inland salt lake, is located in the state of Rajasthan. It is a significant wetland.

Question 4

Which is Satyajit Ray's famous film about the decline of the aristocratic zamindari style of living?

Accepted Answer

Satyajit Ray's 'Jalsaghar' (The Music Room) vividly portrays the decline of an aristocratic zamindar and his opulent lifestyle, making it the correct answer.

Question 5

The perimeter of a right triangle is 60 cm and its hypotenuse is 26 cm. Find the area of the triangle.

Accepted Answer

Let sides be a, b, 26. Perimeter a+b+26=60, so a+b=34. By Pythagoras, a²+b²=26²=676. (a+b)²=a²+b²+2ab => 34²=676+2ab => 1156=676+2ab => 2ab=480 => ab=240. Area = 0.5 * ab = 0.5 * 240 = 120 cm².

Question 6

How manyodd numbers are preceded by the number 4in the following series?2 6 6 3 4 5 2 4 9 8 6 4 3 4 8 2

Accepted Answer

Identify pairs where '4' is immediately followed by an odd number. The pairs are 4-5, 4-9, and 4-3. Thus, there are 3 such instances.

Question 7

The number between 6000 and 7000 that is divisible by each of 12, 21, 32 and 18 is:

Accepted Answer

Find the LCM of 12, 21, 32, and 18, which is 2016. Multiply the LCM by an integer (k) such that the result falls between 6000 and 7000. 2016 * 3 = 6048.

Question 8

If three cubes whose edges measure 3 cm, 4 cm and 5 cm respectively, are melted to form a single cube, then find the edge of the new cube.

Accepted Answer

Calculate the sum of volumes of the three cubes (3³+4³+5³ = 27+64+125 = 216 cm³). The new cube's volume is 216 cm³, so its edge is the cube root of 216, which is 6 cm.

Question 9

The Red Fort of Agra was founded by which Mughal Emperor?

Accepted Answer

Akbar commissioned the construction of the Agra Fort, also known as the Red Fort of Agra, between 1565 and 1573. It served as his primary residence.

Question 10

What is the least possible number which must be subtracted from 16, 19 and 23, so that the resulting numbers are in continued proportion?

Accepted Answer

Let the number be x. For continued proportion, (16-x)/(19-x) = (19-x)/(23-x). Cross-multiply and solve the quadratic equation to find x=7.

Question 11

A 400-m-long train is travelling at a speed of 60 km/h. How much time will it take to cross at 600-m-long bridge?

Accepted Answer

Total distance = train length + bridge length = 400m + 600m = 1000m. Convert speed to m/s: 60 km/h = 60 * (5/18) m/s = 100/3 m/s. Time = Distance/Speed = 1000 / (100/3) = 30 seconds = 1 minute.

Question 12

The sum of two numbers is 16 and their product is 63. The sum of their reciprocal is equal to:

Accepted Answer

Let the numbers be x and y. Given x+y=16 and xy=63. The sum of their reciprocals is 1/x + 1/y = (x+y)/xy. Substitute the given values to get 16/63.

Question 13

Who was the first Indian to win the Nobel Prize for literature in 1913?

Accepted Answer

Rabindranath Tagore was the first Indian and also the first non-European to win the Nobel Prize in Literature in 1913 for his profound collection of poems, 'Gitanjali'.

Question 14

If a2+ b2= 82 and ab = 9, Find the value of a3+ b3.

Accepted Answer

Use the identity (a+b)² = a²+b²+2ab to find (a+b). Then apply a³+b³ = (a+b)(a²-ab+b²) to calculate the final value.

Question 15

(1 -‌1n) + (1 -‌2n) + (1 -‌3n) + up to n term will result as:

Accepted Answer

The series is an arithmetic progression. Sum of n terms is n/2 * (first term + last term). First term is (1-1/n) and last term is (1-n/n) = 0. So, sum = n/2 * (1-1/n + 0) = n/2 * (n-1)/n = (n-1)/2.

Question 16

If the sum of the squares of the zeros of quadratic polynomial f(x) = x2– 8x + k is 40, then find the value of k.

Accepted Answer

Let α and β be the zeros. α+β = 8 and αβ = k. Given α²+β² = 40. Use (α+β)² = α²+β²+2αβ. Substitute values: 8² = 40 + 2k. Solve for k: 64 = 40 + 2k => 2k = 24 => k = 12.

Question 17

Which scheme of the Government of India provides for the delivery of LPG cylinders to the below poverty line (BPL) families?

Accepted Answer

The Pradhan Mantri Ujjwala Yojana (PMUY) was launched to provide LPG connections to women from BPL households, ensuring clean cooking fuel.

Question 18

_______ is the largest bauxite producing state of India.

Accepted Answer

Odisha is the leading producer of bauxite in India, accounting for over half of the country's total production. This is a direct factual recall question.

Question 19

In an isosceles triangle ABC, if AB = AC = 26 cm and BC = 20 cm, find the area of triangle ABC.

Accepted Answer

Draw an altitude from A to BC, bisecting BC. Use Pythagoras theorem to find height (24 cm). Area = 0.5 * base * height = 0.5 * 20 * 24 = 240 cm².

Question 20

Which point on the given number line represents 6/5?

Accepted Answer

Convert the fraction 6/5 to a decimal, which is 1.2. Locate 1.2 on the number line between 1 and 2. Point R is exactly at 1.2.