AP , GP ,HP Test No. 1

Question no. 1

If the n^th term of an A.P. is 2n-1, what is the sum of upto n terms ?
  n²
  n²-1
  n²+1
  0.5n(n+1)

Question no. 2

If the three observation are 3,-6 and -6. Then what is their harmonic mean?
  0
  -3
  -0.5
  ∞

Question no. 3

If the number of terms of an A.P. is (2n+1), then what is the ratio of the sum of odd terms to the even terms?
  n/(n+1)
  n²/(n+1)
  (n+1)/n
  (n+1)/2n

Question no. 4

If the sum of terms of an A.P. is n² -2n , then what is the n^th term?
  3n-n²
  2n-3
  2n+3
  2n-5

Question no. 5

If the AM and GM of two numbers are 5 and 4 respectively, then what is the HM of those numbers?
  5/4
  16/5
  9/2
  9

Question no. 6

If x² , y², z² are in A.P., then y+z, z+x, x+y are in
  AP
  GP
  HP
  None of these

Question no. 7

If x,2x+2,3x+3 are the first three terms of a GP, then what is the 4^TH term?
  -27/2
  27/2
  33/2
  -33/2

Question no. 8

In an AP, the m^th term is 1/n and n^th term is 1/m. What is the (mn)^th term ?
  1/(mn)
  m/n
  n/m
  1

Question no. 9

If p times the pth term of an AP is q times the qth term, then what is the (p+q)th term equal to ?
  p+q
  pq
  1
  0

Question no. 10

If the sum of an infinite G.P. be 9 and the sum of first two terms be 5, then, the common ratio is
  1/3
  3/2
  3/4
  2/3

Question no. 11

If a,b,c are the p^th ,q^th and r^th terms of GP, then (b/a)^r(c/b)^p(a/c)^q is equal to
  1
  a^pb^qc^r
  a^qb^rc^p
  a^rb^pc^q

Question no. 12

If x, y, z are in A.P., then y+z, z+x, x+y are in
  AP
  GP
  HP
  None of these

Question no. 13

The sums of n terms of A.P. are in the ratio 2n+3 : 6n+5, then the ratio of their 13th terms is
  53:155
  27:77
  29:83
  31:89

Question no. 14

Find the sum of first n terms of the series : 1(1)! + 2(2)! + 3(3)! + ...............
  n! -1
  (n+1)! +1
  (n+1)! -1
  n! + 1

Question no. 15

If log₃2, log₃(2^x-5) and log₃(2^x-7/2) are in A.P. , then the value of x is
  1, 1/2
  1, 1/3
  1, 3/2
  none of these