ECAT Pre Engineering MCQ Test With Answer for Chapter 8 Mathematics

The next term of the sequence 1, 2, 4, 7, 11, ..... is.

• 15 A
• 16 B
• 17 C
• 18 D

The A.M. of two numbers is 34 and G.M. is 16, the numbers are

• 2 and 64 A
• 64 and 3 B
• 64 and 4 C
• None of these D

If Sn is a definite number as n → ∞,then the geometric series is

• Convergent A
• Divergent B
• Oscillatroy C
• None of these D

If p, q, r and in A.P., a is G.M. between p and q and b is G.M. between q and r, then a², q², b²are in

• A.P. A
• G.P. B
• H.P. C
• None of these D

How many numbers are there between 103 and 750 which are divisible by 6

• 125 A
• 107 B
• 108 C
• 113 D

If A is such that a,A,B are in A.P then A is called

• A.M A
• Common ratio B
• Common difference C
• None of these D

What is the 26th term of the sequence, if its general term is a_{n = (-1)}ⁿ⁺¹

• 2 A
• 26 B
• 27 C
• 1 D

Let S_ndenote the sum of the first n terms of an A.P. If S_2n= 3 S_n: S_nis equal to

• 4 A
• 6 B
• 8 C
• 10 D

A Series which does not coverage to a Unique sum is called

• Harmonic Series A
• Oscillatroy Series B
• Arithmetic Series C
• None of these D

1,1/3,1/5,1/7,1/9..... is a

• geometric sequence A
• finite sequence B
• infinite sequence C
• arithmetic series D

A Geometric Series is divergent only if

• |r|>1 A
• |r|≥1 B
• |r|=1 C
• None of these D

If #n = (n-5)2 + 5, then find #3 x #4.

• 54 A
• 12 B
• 4 C
• 9 D

A number A is called the arithmetic mean between a and b if a, A, b is ______

• Arithmetic sequence A
• Geometric sequence B
• Harmonic sequence C
• Arithmetic sequence D

The harmonic mean between a and b is

• 
  A
• 
  B
• 
  C
• 
  D

An infinite arithmetic series is always

• Convergent A
• Oscillatory B
• Divergent C
• None of these D

The third term of the sequence a_n= (-1)^n-1(n-7) is ______

• 8 A
• 4 B
• -4 C
• 8 D

The sum of an infinite geometric series exist if

• | r | < 1 A
• | r | > 1 B
• r = 1 C
• r = -1 D

If a₁and r are the first term and the common ratio respectively then (n + 1)th term of the G.P. is

• 0 A
• a₁r^n-1 B
• a₁rⁿ⁺¹ C
• a₁rⁿ D

Arithmetic mean between a and b is

• 
  A
• 
  B
• 
  C
• 
  D

• 
  A
• 
  B
• 
  C
• 
  D

If all members of a sequence are real numbers then it is called

• A.P A
• Real Sequence B
• G.P C
• None of these D

The 7th term of the A.P 7,11,15,is

• 24 A
• 31 B
• 26 C
• 23 D

A sequence of number whose reciprocals form an arithmetic sequence is called

• Geometric sequence A
• Arithmetic series B
• Harmonic sequence C
• Harmonic series D

If a, b, c are in A.P., then 3^a, 3^b, 3^care in

• A.P. A
• G.P. B
• H.P. C
• None of these D

The third term of a G.P. is the square of first term. If the second term is 8, then the 6th term is

• 120 A
• 124 B
• 128 C
• 132 D

An A.P., a G.P. and a H.P. have the same first and last terms and the same odd numbers of terms, the middle terms of the three series are in

• A.P. A
• G.P. B
• H.P. C
• None of these D

An A.P. consists of n(odd terms) and its middle term is m. then the sum of the A.P. is

• 2 mn A
• 1/2 mn B
• mn C
• mn² D

The sum of infinite numbers of terms of an arithmetic series is

• Finite A
• Infinite B
• May or may not finite C
• None of these D

If a, b, c are in AP., a, b, c are in G.P. then A, m²b, c are in

• A.P. A
• G.P. B
• H.P. C
• None of these D

If all members of a sequence are real numbers then it is called a

• Series A
• Function B
• Real sequence C
• Range D