Algebra (Railway Maths) (Part – IX)

Total Questions: 50

1. If x = 25 and y = 13 then find √(x² - 2xy + y²) [RRB NTPC 15/03/2021 (Morning) ]

Correct Answer: (a) 12
Solution:

2. If a²ˣ = b, b²ʸ = c, c²ᶻ = a then the value of xyz is: [RRB NTPC 15/03/2021 (Evening)]

Correct Answer: (d) 1/8
Solution:

3. What is the value of 99³? [RRB NTPC 19/03/2021 (Morning)]

Correct Answer: (d) 970299
Solution:

99³ = 99 × 99 × 99 = 970299

4. If 2x + 3y = 23 and x = 4, then what is the value of y? [RRB NTPC 19/03/2021 (Morning)]

Correct Answer: (c) 5
Solution:

2x + 3y = 23
⇒ 2 × 4 + 3y = 23 ⇒ 8 + 3y = 23
⇒ 3y = 15 ⇒ y = 5

5. Find the value of (p - q)³ + (q - r)³ + (r - p)³ / 9(p - q)(q - r)(r - p). [RRB NTPC 19/03/2021 (Evening)]

Correct Answer: (d) 1/3
Solution:

6. If a⁴ + b⁴ = 17 and a + b = 1, then the value of a²b² - 2ab is: [RRB NTPC 19/03/2021 (Evening)]

Correct Answer: (c) 8
Solution:

7. Find the value of (?) in the following: (a² - b²) : (a² - ab) : : (a³ + b³) : ? [RRB NTPC 19/03/2021 (Evening) ]

Correct Answer: (c) a(a² + b² - ab)
Solution:

8. Find the value of (x + y)², if x = √(2 + √3) / √(2 - √3) and y = √(2 - √3) / √(2 + √3). [RRB NTPC 19/03/2021 (Evening)]

Correct Answer: (b) 100
Solution:

9. Find the remainder when x³ + 4x² + 6x - 2 is divided by (x + 5). [RRB NTPC 21/03/2021 (Morning)]

Correct Answer: (c) -57
Solution:

10. If x - 1/x = √21, find the positive value of (x² + 1/x²) (x + 1/x). [RRB NTPC 21/03/2021 (Morning)]

Correct Answer: (b) 115
Solution: