Quiz Discussion

After striking the floor, a rubber ball rebounds to 4/5th of the height from which it has fallen. Find the total distance that it travels before coming to rest if it has been gently dropped from a height of 120 metres.

• 1] 540 m
• 2] 960 m
• 3] 1080 m
• 4] 1020 m
• 5] 1120 m

The 3rd and 8th term of an arithmetic progression are -13 and 2 respectively. What is the 14th term?

• 1] 23
• 2] 17
• 3] 20
• 4] 26

Consider an infinite G.P. with first term a and common ratio r, its sum is 4 and the second term is 3/4, then

• 1]

  a = 7/4, r = 3/7

• 2]

  a = 2, r = 3/8

• 3]

  a = 3, r = 1/4

• 4]

  a = 3/2, r = ½

(1) + (1 + 1) + (1 + 1 + 1) + ....... + (1 + 1 + 1 + ...... n - 1 times) = ......

• 1]

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

• 2]

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

• 3]

  \({n^2}\)

• 4]

  n

The sum of the first and third term of an arithmetic progression is 12 and the product of first and second term is 24, then first term is

• 1]

  4

• 2]

  1

• 3]

  8

• 4]

  6

If Sn denote the sum of the first n terms of an A.P. If S2n = 3Sn , then S3n : Sn is equal to

• 1] 4
• 2] 6
• 3] 8
• 4] 10

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] 214

The 3rd and 6th term of an arithmetic progression are 13 and -5 respectively. What is the 11th term?

• 1] -29
• 2] -41
• 3] -47
• 4] -35

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

The 3rd and 9th term of an arithmetic progression are -8 and 10 respectively. What is the 16th term?

• 1] 34
• 2] 28
• 3] 25
• 4] 31