Business Mathematics

211. Find the term independent of x in the expansion of (x2 + 1/x)9

  1. 6 th term
  2. 8th term
  3. 7 th term
  4. 8th term
Correct answer: (C)
7 th term

212. The probability that a man will live 10 years is ¼ and the probability that his wife will live 10 more years is 1/3. Then the probability that neither will be alive in 10 years as

  1. 5/12
  2. 7/12
  3. ½
  4. 11/12
Correct answer: (C)
½

213. Solve a + b + c +d =1
-a + b -d = 1
a -b +c = 1
b +c = 1

  1. a= 2, b= 1, c= 0, d=-2
  2. a=1, b=2, c=0, d=2
  3. a=2, b=0, c=0, d=-2
  4. a=1, b=1, c=-2, d=2
Correct answer: (A)
a= 2, b= 1, c= 0, d=-2

214. Solve x -3y +6z = -1
2x -5y +10z = 0
3x -8y +17z = 1

  1. x=4, y=5, z=1
  2. x=2, y=3, z=6
  3. x=5, y=6, z=2
  4. x=5, y=3, z=6
Correct answer: (C)
x=5, y=6, z=2

215. Exogenous variables of a matrix are called

  1. Endogenous variables
  2. Dependent variables
  3. Mixed variables
  4. Independent variables
Correct answer: (D)
Independent variables

216. The number of all possible matrices of order 3x3 with each entry 0 or 1 is:

  1. 27
  2. 18
  3. 81
  4. 512
Correct answer: (D)
512

217. If A is a square matrix such that A2 = A, then (I + A )3 -7A is equal to

  1. A
  2. I – A
  3. I
  4. 3A
Correct answer: (C)
I

218. Matrices A and B will be inverse of each other only if

  1. AB = BA
  2. AB =BA = 0
  3. AB =0, BA =I
  4. AB = BA = I
Correct answer: (D)
AB = BA = I

219. Find values of k if area of triangle is 4sq. units and vertices are (k, 0), (4,0), (0,2)

  1. 0, 8
  2. 8, 0
  3. 0, 0
  4. 8, 8
Correct answer: (A)
0, 8

220. Equation of line joining (3,1), and(9,3) using determinants are

  1. x -3y =0
  2. x +3y =0
  3. y +3x =0
  4. y -3x =0
Correct answer: (a)
x -3y =0
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