Quiz Discussion

In an A.P., if d = -4, n = 7, an = 4, then a is

• 1] 6
• 2] 7
• 3] 20
• 4] 28

The sum of the first 16 terms of an AP whose first term and third term are 5 and 15 respectively is

• 1] 600
• 2] 765
• 3] 640
• 4] 680
• 5] 690

Which term of the A.P. 92, 88, 84, 80, ...... is 0?

• 1] 23
• 2] 32
• 3] 22
• 4] 24

If 18th and 11th term of an A.P. are in the ratio 3 : 2, then its 21st and 5th terms are in the ratio

• 1] 3 : 2
• 2] 3 : 1
• 3] 1 : 3
• 4] 2 : 3

The sum of first n odd natural numbers in

• 1] 2n - 1
• 2] 2n + 1
• 3] n2
• 4] n2 - 1

Find the n^th term of the following sequence :
5 + 55 + 555 + . . . . T_n

• 1]

   

  5(10ⁿ - 1) 

• 2]

   

  5ⁿ(10ⁿ - 1)

• 3]

  5/9×(10ⁿ−1)

     

• 4]

  (5/9)ⁿ×(10ⁿ−1)

If an A.P. has a = 1, tn = 20 and sn = 399, then value of n is :

• 1] 20
• 2] 32
• 3] 38
• 4] 40

The two geometric means between the number 1 and 64 are

• 1]

  8 and 16

• 2]

  2 and 16

• 3]

  4 and 8

• 4]

  4 and 16

Find the first term of an AP whose 8th and 12th terms are respectively 39 and 59.

• 1] 5
• 2] 6
• 3] 4
• 4] 3
• 5] 7

What is the sum of the first 12 terms of an arithmetic progression if the first term is -19 and last term is 36?

• 1]

  192

• 2]

  230

• 3]

  102

• 4]

  204