**Geometric Series:**

Geometric Number series is a arrangement of numbers in a certain order, where **some numbers are this type of series are based on ascending or descending order of numbers and each continues number is obtain by multiplication or division of the previous number with a static number.**

we need to observe and find the accurate number to the series of numbers. This type of problem are given in Quantitative Aptitude which is a very essential in banking exam. Under below given some more example for your better practice.

In geometric series number is a combination of number arranged. In example 1) 5, 45, 405, 3645, ? where you need to count them in a one step or two step calculation for obtain the difference common result according with the series of numbers.

At first you can calculate missing number in geometric series and that you place the actual missing number in the ? or missing place. Be prepared when you calculate differences because it is either one or two step calculation. So when you calculate and get result of two difference numbers you need follow some step wise.

At first calculate the first number 5 with 9 and second number value we get that is 45 then again second number calculate multiply with 9 and get the third number and follow same steps which is carry up to last and after that you get actual missing number by finding the common value when you put the missing number you have noticed that all series numbers are common 9 which multiply with number and get next number difference.

This kind of missing series calculation you go thorough some common calculation shortcut tricks using cube multiplication division addition cube square shortcut tricks.

In this type series example questions, it is sounds hard, but it really isn’t. Get it? Once you have done this, by practice with more example then you just easily can do in your way as well competitive and as in bank exam also. So, each of our examples are given below.

Example #1

3, ? , 45, 144, 585

- 18
- 21
- 23
- 27

Show Answer Show How to Solve Open Rough Workspace

**Answer:**Option (A)

**How to Solve**

3 x 0 + 9 = 9

**9 x 1 + 9 = 18**

18 x 2 + 9 = 45

45 x 3 + 9 = 144

144 x 4 + 9 = 585

**Rough Workspace**

Example #2

5, 45, 405, 3645, ?

- 26832
- 28667
- 30551
- 32805

Show Answer Show How to Solve Open Rough Workspace

**Answer:**Option (D)

**How to Solve**

5 x 9 = 45

45 x 9 = 405

405 x 9 = 3645

**3645 x 9 = 32805**

**Rough Workspace**

Example #3

73205, 6655, 605, 55, ?

- 3
- 4
- 5
- 7

Show Answer Show How to Solve Open Rough Workspace

**Answer:**Option (C)

**How to Solve**

**5**

5 x 11 = 55

55 x 11 = 605

605 x 11 = 6655

6655 x 11 = 73205

**Rough Workspace**

Example #4

21, 84, 336, ? , 5376

- 1344
- 1262
- 1173
- 1061

Show Answer Show How to Solve Open Rough Workspace

**Answer:**Option (A)

**How to Solve**

21 x 4 = 84

84 x 4 = 336

**336 x 4 = 1344**

1344 x 4 = 5376

**Rough Workspace**

Example #5

9, 54, ? , 1944, 11664

- 226
- 324
- 381
- 753

Show Answer Show How to Solve Open Rough Workspace

**Answer:**Option (B)

**How to Solve**

9 x 6 = 54

**54 x 6 = 324**

324 x 6 = 1944

1944 x 6 = 11664

**Rough Workspace**

Example #6

5, 35, ? , 1715, 12005

- 205
- 245
- 503
- 976

Show Answer Show How to Solve Open Rough Workspace

**Answer:**Option (B)

**How to Solve**

5 x 7 = 35

**35 x 7 = 245**

245 x 7 = 1715

1715 x 7 = 12005

**Rough Workspace**

Example #7

25, 100, ? , 1600, 6400

- 800
- 600
- 500
- 400

Show Answer Show How to Solve Open Rough Workspace

**Answer:**Option (D)

**How to Solve**

25 x 4 = 100

**100 x 4 = 400**

400 x 4 = 1600

1600 x 4 = 6400

**Rough Workspace**

Example #8

6, 18, 54, ? , 486, 1458

- 124
- 162
- 188
- 360

Show Answer Show How to Solve Open Rough Workspace

**Answer:**Option (B)

**How to Solve**

6 x 3 = 18

18 x 3 = 54

**54 x 3 = 162**

162 x 3 = 486

486 x 3 = 1458

**Rough Workspace**

Example #9

15, 30, 60, 120, ?

- 180
- 220
- 240
- 310

Show Answer Show How to Solve Open Rough Workspace

**Answer:**Option (C)

**How to Solve**

15 x 2 = 30

30 x 2 = 60

60 x 2 = 120

**120 x 2 = 240**

**Rough Workspace**

Example #10

19, ? , 475, 2375, 11875

- 88
- 90
- 93
- 95

Show Answer Show How to Solve Open Rough Workspace

**Answer:**Option (D)

**How to Solve**

**19 x 5 = 95**

475 x 5 = 2375

2375 × 5 = 11875

**Rough Workspace**

Example #11

3, 48, ? , 768, 3072

- 192
- 221
- 390
- 556

Show Answer Show How to Solve Open Rough Workspace

**Answer:**Option (A)

**How to Solve**

3 x 4 = 12

12 x 4 = 48

**48 x 4 = 192**

192 x 4 = 768

768 x 4 = 3072

**Rough Workspace**

### Other Types of Number Series

- Perfect Square Series
- Ration Series
- Mixed Series
- Perfect Cube Series
- << Go back to Number Series main page

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you are providing easy tricks and very useful

3*0+9=12???

3*0+9=9

0+9=9

ya u r right, how it is possible

i m definetly agree with you.according the VODMAS formula multiplication should take first place and than we can do addition.so the answer should be 3*0+9=9

wait

thank u sir

Hi , could you mail me all the shortcuts

Sir hard level ke exanple batao please

3*0+9=9

How its 12??

please recheck the problem

Its too simple.

Get something to make us scratch ours heads!