Arithmetic and Geometric Progressions

You are here: Home  CAT Questionbank   CAT Quant  AP, GP  Question 18
Sequence and Series

Sum of Series

    Find the sum of the series .4 + .44 + .444……. to n terms
    1. 5.69
    2. 14.44


  • Correct Answer
    Choice C.

Detailed Solution

.4 + .44 + .444+……. to n terms

= 4x[0.1 +0.11 +0.111+…… n terms]

= * [0.9 +0.99 + 0.999+…….to n terms] (Multiplying and dividing by 9)

= * [(1-0.1)+(1-0.01)+(1-0.001)+…….to n terms]

= * [(1+1+1… n terms)-(0.1+0.01+0.001…to n terms)]






Correct Answer:

Our Online Course, Now on Google Playstore!

2IIM's App

Fully Functional Course on Mobile

All features of the online course, including the classes, discussion board, quizes and more, on a mobile platform.

Cache Content for Offline Viewing

Download videos onto your mobile so you can learn on the fly, even when the network gets choppy!

Get it on Google Play

More questions from Progressions

  1. Counting and Progressions
  2. Common Ratio
  3. Common Difference
  4. Sum up to 'n' Terms
  5. AP Puzzle
  6. GP Logical Puzzle
With some simple but very powerful ideas, one can cut down on a lot of working when it comes to progressions. For example, anchoring a progression around its middle term can be very useful. Reinforce these ideas with these questions.