RRB NTPC 2021 PYQs

Question 1

PQRS is a cyclic trapezium where PQ is parallel to RS and PQ is the diameter. If ∠QPR = 40° then the ∠PSR is equal to:

Accepted Answer

Since PQ is the diameter, ∠PRQ = 90°. In ΔPQR, ∠PQR = 180° - 90° - 40° = 50°. As PQRS is a cyclic quadrilateral, ∠PSR + ∠PQR = 180°. So, ∠PSR = 180° - 50° = 130°.

Question 2

Observe the graph and answer the question below.The graph represents the number of male and female workers in four different companies.Which company has the maximum difference in the number of male and female employees?

Accepted Answer

Calculate the absolute difference between male and female workers for each company from the graph. Company D has the largest difference (70-30=40), making it the correct answer.

Question 3

If x2- 4x + 1 = 0, then what is the value ofx2+‌1x2?

Accepted Answer

Divide the given equation by x to get x + 1/x = 4. Then square both sides: (x + 1/x)^2 = 4^2, which simplifies to x^2 + 1/x^2 + 2 = 16. Thus, x^2 + 1/x^2 = 14.

Question 4

Which sector is the biggest emitter of greenhouse gases?

Accepted Answer

The energy sector, encompassing electricity, heat, and transport, is globally the largest contributor to greenhouse gas emissions due to fossil fuel combustion.

Question 5

Study the given pie chart carefully and answer the question.The given pie chart represents the data of Amit's followers on various social networking sites.If Amit has 40 crore followers in all the networking sites combined, then the number of his followers on Facebook will be:

Accepted Answer

Facebook accounts for 32% of total followers. Calculate 32% of 40 crore. (32/100) * 40 = 12.8 crore followers.

Question 6

Study the following bar graph and answer the question that follows.In which year was the number of accounts approximately 15% of the total number of accounts in all the years.

Accepted Answer

Calculate the total accounts (200+250+300+350+400 = 1500). Find 15% of 1500, which is 225. The year with approximately 225 accounts is Mar 2010 (200 accounts).

Question 7

Directions (Qs 86-89): Study the given table and answer the question that follows.
This table shows the number of jobs created during the period 1940 - 1979.
Year
Job Creation
(Millions)
1940
70
1944
80
1950
60
1958
55
1970
90
1979
75

In which of the following three years was the number of jobs created higher than the average job creation during the period 1940-79.

Accepted Answer

First, calculate the average job creation from 1940-79. Then, identify the years from the options where job creation exceeded this average. Option 4 lists three such years.

Question 8

According to the given table, what is the number of students in 11thstandard who passed?ClassSubjectsPass % of StudentsNo. of Failed Students10thMaths6510510thHindi8012011thEnglish4036012thPsychology7510012thBiology50110

Accepted Answer

For 11th English, 40% passed, meaning 60% failed. If 360 students failed (60%), then total students are 360 / 0.60 = 600. Passed students are 600 - 360 = 240.

Question 9

If 'A + B' means 'A is daughter of B', 'A - B' means 'A is wife of B', 'A × B' means 'A is the son of B', If P × Q - S then which of the following is true?

Accepted Answer

P × Q means P is the son of Q. Q - S means Q is the wife of S. Therefore, S is the husband of Q and the father of P.

Question 10

A question and three statements labelled (I), (II) and (III) are given. You have to decide which statement(s) is/are sufficient to answer the question.Question: Who is the shortest among A, B, C, D and E?Statements:I. A is taller than E but shorter than D.II. B is shorter than C but taller than E.III. D is taller than C and A is taller than B.

Accepted Answer

From statement I: D > A > E. From statement II: C > B > E. Combining these, E is the shortest as both A and B are taller than E, and D and C are taller than A and B respectively.

Question 11

The addition to capital stock in an economy is measured by net investment or new capital formation, which is expressed as:

Accepted Answer

Net investment is calculated by subtracting depreciation (wear and tear of capital) from gross investment. This formula accounts for the actual increase in capital stock.

Question 12

Select the number that will come next in the following series.2, 7, 14, 23, ?

Accepted Answer

The differences between consecutive terms are 5, 7, 9. This is an arithmetic progression with a common difference of 2. The next difference should be 11. So, 23 + 11 = 34.

Question 13

Directions (Qs 86-89): The following table shows the points scored by four players in four games:
Player
Game1
Game2
Game3
Game4
A
12
8
10
6
B
0
8
6
4
C
8
11
4
3
D
10
12
2
8

Determine the average number of points scored by A, considering all the games.

Accepted Answer

To find the average, sum all points scored by A and divide by the number of games. (10+8+12+6)/4 = 36/4 = 9.

Question 14

Study the following bar graph and answer the question that follows.What is the approximate difference in the number of accounts for March 2010 and March 2011 as a percentage of the total number of accounts represented in the graph?

Accepted Answer

Calculate the difference between March 2010 (300) and March 2011 (400), which is 100. The total accounts are 1600. Percentage difference is (100/1600) * 100 = 6.25%, approximately 6%.

Question 15

Directions (Qs 86-89): Study the given table and answer the question that follows.
This table shows the number of jobs created during the period 1940 - 1979.
Year
Job Creation
(Millions)
1940
70
1944
80
1950
60
1958
55
1970
90
1979
75

From the given options, the highest average number of jobs created were in which 3 years?

Accepted Answer

Identify the job creation numbers for each year in the options. Sum the values for each option and divide by three to find the average. The option with the highest average is the correct answer.

Question 16

According to the given table, what is the percentage of the total students who failed considering all the three classes i.e. 10th, 11thand 12thand in all five given subjects?ClassSubjectsPass % of StudentsNo. of Failed Students10thMaths6510510thHindi8012011thEnglish4036012thPsychology7510012thBiology50110

Accepted Answer

Calculate total failed students (105+120+360+100+110 = 795). For each subject, find total students using failed count and pass percentage. Sum total students. Divide total failed by total students and multiply by 100.

Question 17

Select the letter-cluster from among the given options that can replace the question mark (?) in the following series.ACDF, GIJL, MOPR, ?

Accepted Answer

The pattern is +6 for the first letter, +6 for the second, +6 for the third, and +6 for the fourth letter of each cluster. Applying this to MOPR (M+6=S, O+6=U, P+6=V, R+6=X) gives SUVX.

Question 18

Read the given statements and conclusions carefully. Assuming that the information given in the statements is true, even if it appears to be at variance with commonly known facts, decide which of the given conclusions logically follows(s) from the statements.Statements:1. All the case are four-wheelers.2. All the four-wheelers are vehicles.Conclusions:I. All the vehicle are four-wheelersII. All the case are vehicles.

Accepted Answer

From 'All Case are Four-wheelers' and 'All Four-wheelers are Vehicles', it logically follows that 'All Case are Vehicles'. Conclusion I is a converse fallacy.

Question 19

If A is taller than B and B is taller than C. D is shorter than B but taller than C, then D is:

Accepted Answer

From the given statements, we establish the order: A > B > D > C. Therefore, D is taller than C.

Question 20

Directions (Qs 86-89): The following table shows the points scored by four players in four games:
Player
Game1
Game2
Game3
Game4
A
12
8
10
6
B
0
8
6
4
C
8
11
4
3
D
10
12
2
8

Who is the overall worst performer considering all four games?

Accepted Answer

Sum the scores for each player across all four games. Player B has the lowest total score, indicating the worst overall performance.