Mathematics NDA/NA SOLVED PAPER 2019 (II) (01 to 50)

Total Questions: 50

31. Let a, b, c be in AP and k ≠ 0 be a real number. Which of the following are correct?

Correct Answer: (d) 1, 2 and 3
Solution:

32. How many two-digit numbers are divisible by 4?

Correct Answer: (b) 22
Solution:

33. Let Sn be the sum of the first n terms of an AP. If S₂ₙ = 3n + 14n², then what is the common difference?

Correct Answer: (c) 7
Solution:Put n = 1, 2.......
T₁ = 7(1) - 2 = 5
T₂ = 7(2) - 2 = 12
d = T₂ - T₁ = 12 - 5 = 7

34. If 3rd, 8th and 13th terms of a GP are p q, and r respectively, then which one of the following is correct?

Correct Answer: (a) q² = pr
Solution:

35. Find the answer of given question?

Correct Answer: (c)
Solution:

36. Find the answer of given question?

Correct Answer: (b)
Solution:

37. How many real roots does the equation x² + 3 |x| + 2 = 0 have?

Correct Answer: (a) Zero
Solution:

38. Consider the following statements in respect of the quadratic equation 4(x - p) (x - q) - r² = 0.

where p q, and r are real numbers.
1. The roots are real.
2. The roots are equal, if p = q and r = 0.
Which of the above statements is/are correct?

Correct Answer: (c) Both 1 and 2
Solution:

39. Let S = {2, 4, 6, 8,............,20}. What are the maximum number of subsets of S?

Correct Answer: (d) 1024
Solution:

40. A binary number is represented by (cdccddcccddd)₂, where c > d. What is its decimal equivalent?

Correct Answer: (d) 2872
Solution: