Quiz Discussion

The first and last term of an A.P. is a and l respectively. If S is the sum of all the terms of the A.P. and the common difference is given by \(\frac{{{l^2} - {a^2}}}{{k - \left( {l + a} \right)}}\)   then k = ?

• 1] S
• 2] 2S
• 3] 3S
• 4] None of these

Sum of n terms of the series \(\sqrt 2   +   \sqrt 8   +   \sqrt {18}   +   \sqrt {32}   +  \) ....... is

• 1]

  \(\frac{{n\left( {n + 1} \right)}}{2}\)

• 2]

  \(2n\left( {n + 1} \right)\)

• 3]

  \(\frac{{n\left( {n + 1} \right)}}{{\sqrt 2 }}\)

• 4]

  1

15th term of A.P., x - 7, x - 2, x + 3, ........ is

• 1] x + 63
• 2] x + 73
• 3] x + 83
• 4] x + 53

The sum of first five multiples of 3 is:

• 1] 45
• 2] 65
• 3] 75
• 4] 90

For an A.P. if a25 - a20 = 45, then d equals to:

• 1] 9
• 2] -9
• 3] 18
• 4] 23

What is the sum of the first 11 terms of an arithmetic progression if the 3rd term is -1 and the 8th term is 19?

• 1] 204
• 2] 121
• 3] 225
• 4] 104

How many 2-digit positive integers are divisible by 4 or 9?

• 1]

  32

• 2]

  22

• 3]

  34

• 4]

  30

If the fifth term of a GP is 81 and first term is 16, what will be the 4th term of the GP?

• 1] 36
• 2] 18
• 3] 54
• 4] 24
• 5] 27

What is the sum of the first 17 terms of an arithmetic progression if the first term is -20 and last term is 28?

• 1] 68
• 2] 156
• 3] 142
• 4] 242

If 7 times the seventh term of an Arithmetic Progression (AP) is equal to 11 times its eleventh term, then the 18th term of the AP will be

• 1] 0
• 2] 1
• 3] 2
• 4] -1