ECAT Pre Engineering MCQ Test With Answer for Chapter 8 Mathematics

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

• 24 A
• 31 B
• 26 C
• 23 D

An infinite arithmetic series is always

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

The three consecutive numbers a,√ab,b are in

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

If a,b,c are in arithmetic progression, then 1/a,1/b.1/c are in

• A.M A
• G.M B
• H.M C
• G.P D

• 1/2 A
• 2 B
• 1/4 C
• 4 D

A,G,H are in

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

• 
  A
• 
  B
• 
  C
• 
  D

For three consecutive terms in A.P middle term is called

• A.M A
• nth term B
• Central term C
• None of these D

A sequence is a functions whose domain is a subset of the set of

• Natural numbers A
• Real numbers B
• Whole numbers C
• Rational numbers D

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

If a^x= b^y= c^zand a, b, c are in G.P. then x, y, z are in

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

If a_n= 2n -3, write the first four terms

• -3, -1, 1, 3 A
• 1, 3, 5, 7 B
• -1, 1, 3, 5 C
• None of these D

if a_{9 =19,a9=31 are the 6th and 9th term of an A.P. and d=4 is the common difference, then 18th term of the sequence is}

• 65 A
• 67 B
• 71 C
• 75 D

An indicated sum of terms of a sequence is represented by

• Sn A
• an B
• S(n) C
• {Sn} D

Which term of the A.P 5,8,11,24.............is 320

• 104th A
• 106th B
• 105th C
• 64th D

• 
  A
• 
  B
• 
  C
• 
  D

If three unequal numbers p, q, r are in H.P. and their squares are in A.P., then the ration p : q : r is

• 
  A
• 
  B
• 
  C
• 
  D

The fifth term of an A.P. Whose first term is 5 and common difference is 3,is

• 20 A
• 17 B
• 25 C
• 30 D

• 
  A
• 
  B
• 
  C
• 
  D

Geometric mean between a and b is

• 
  A
• 
  B
• 
  C
• 
  D

If 5,7 and 9 are A.Ms between a and b, then a and b is equal to

• 2 and 12 A
• 1 and 10 B
• 3 and 11 C
• -7 and 2 D

an - an-1 will be common difference in an A.P if

• n = 1∀n∈ N A
• n>1∧n∈N B
• n∈Z C
• None of the above D

The sum of the squares of three distinct real numbers, which are in G.P., is S². if their sum isαS then

• 
  A
• 
  B
• 
  C
• 
  D

For an A.P common difference d

• Can be zero A
• May or may not zero B
• Cannot be zero C
• None of these D

1 + 2 + 3 + ...... + n = ______

• 
  A
• 
  B
• 
  C
• 
  D

The common ration of a geometric sequence cannot be

• 0 A
• 1 B
• 2 C
• 3 D

Which one represents a sequence

• an A
• Sn B
• a(n) C
• {an} D

A Geometric Series is divergent only if

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

The number of divisors of 1029, 1547 and 122 are in

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