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# Geometric Series

## Geometric Series

Geometric 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.

### Geometric Series

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 – Geometric Series

3, ? , 45, 144, 585

1. 18
2. 21
3. 23
4. 27

Show Answer Show How to Solve Open Rough Workspace

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 – Geometric Series

5, 45, 405, 3645, ?

1. 26832
2. 28667
3. 30551
4. 32805

Show Answer Show How to Solve Open Rough Workspace

How to Solve
5 x 9 = 45
45 x 9 = 405
405 x 9 = 3645
3645 x 9 = 32805
Rough Workspace

### Example #3 – Geometric Series

73205, 6655, 605, 55, ?

1. 3
2. 4
3. 5
4. 7

Show Answer Show How to Solve Open Rough Workspace

How to Solve
5
5 x 11 = 55
55 x 11 = 605
605 x 11 = 6655
6655 x 11 = 73205
Rough Workspace

### Example #4 – Geometric Series

21, 84, 336, ? , 5376

1. 1344
2. 1262
3. 1173
4. 1061

Show Answer Show How to Solve Open Rough Workspace

How to Solve
21 x 4 = 84
84 x 4 = 336
336 x 4 = 1344
1344 x 4 = 5376
Rough Workspace

### Example #5 – Geometric Series

9, 54, ? , 1944, 11664

1. 226
2. 324
3. 381
4. 753

Show Answer Show How to Solve Open Rough Workspace

How to Solve
9 x 6 = 54
54 x 6 = 324
324 x 6 = 1944
1944 x 6 = 11664
Rough Workspace

### Example #6 – Geometric Series

5, 35, ? , 1715, 12005

1. 205
2. 245
3. 503
4. 976

Show Answer Show How to Solve Open Rough Workspace

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

1. 800
2. 600
3. 500
4. 400

Show Answer Show How to Solve Open Rough Workspace

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

1. 124
2. 162
3. 188
4. 360

Show Answer Show How to Solve Open Rough Workspace

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, ?

1. 180
2. 220
3. 240
4. 310

Show Answer Show How to Solve Open Rough Workspace

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

1. 88
2. 90
3. 93
4. 95

Show Answer Show How to Solve Open Rough Workspace

How to Solve
19 x 5 = 95
475 x 5 = 2375
2375 × 5 = 11875
Rough Workspace

### Example #11

3, 48, ? , 768, 3072

1. 192
2. 221
3. 390
4. 556

Show Answer Show How to Solve Open Rough Workspace

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

If you have any question regarding this topic then please do comment on below section. You can also send us message on facebook.

1. mohana says:

you are providing easy tricks and very useful

2. M.MOHAN KUMAR says:

3*0+9=12???
3*0+9=9
0+9=9

• rupesh says:

ya u r right, how it is possible

• tanisha roy says:

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

• manikandan says:

wait

3. chinnasamy says:

thank u sir

4. Manogna says:

Hi , could you mail me all the shortcuts

5. mahendra rathore says:

Sir hard level ke exanple batao please

6. krishma says:

3*0+9=9
How its 12??

• 7. 8. 