Quiz Discussion

A boy agrees to work at the rate of one rupee on the first day, two rupees on the second day, and four rupees on third day and so on. How much will the boy get if he started working on the 1st of February and finishes on the 20th of February?

• 1] 220
• 2] 220 -1
• 3] 219 -1
• 4] 219
• 5] None of these

If the sums of n terms of two arithmetic progressions are in the ratio \(\frac{{3n + 5}}{{5n + 7}}\)   then their nth terms are in the ration

• 1]

  \(\frac{{3n - 1}}{{5n - 1}}\)

• 2]

  \(\frac{{3n + 1}}{{5n + 1}}\)

• 3]

  \(\frac{{5n + 1}}{{3n + 1}}\)

• 4]

  \(\frac{{5n - 1}}{{3n - 1}}\)

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

If the nth term of an A.P. is 2n + 1, then the sum of first n terms of the A.P. is

• 1] n(n - 2)
• 2] n(n + 2)
• 3] n(n + 1)
• 4] n(n - 1)

The sum of the first four terms of an A.P. is 56. The sum of the last four terms is 112. If its first term is 11, the number of terms is

• 1]

  10

• 2]

  11

• 3]

  12

• 4]

  13

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

The sum of first five multiples of 3 is:

• 1] 45
• 2] 65
• 3] 75
• 4] 90

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

• 1] 23
• 2] 32
• 3] 22
• 4] 24

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

Two A.P.’s have the same common difference. The first term of one of these is 8 and that of the other is 3. The difference between their 30th terms is

• 1] 11
• 2] 3
• 3] 8
• 4] 5