Please explain : Complete the series
 

[QUOTE]1. 18 20 24 32 ans 48
2. 212 179 146 113 ans 80
3. 6 8 10 14 ans 18
4. 4 20 35 49 ans 62
5. 6 11 20 37 ans 70
6. 1 3 9 27 ans 81[/QUOTE]


please somebudy explain these questions.i dont such kind of questions?

[QUOTE=mashal khan;169791]please somebudy explain these questions.i dont such kind of questions?[/QUOTE]
1. 18 20 24 32 ans 48 (difference first 2 then 4 then 8 then 16 so thats why its 48 after 32)

2. 212 179 146 113 ans 80
(subtracting 33 from each term)

3. 6 8 10 14 ans 18
(first ad 2 in 6 then add 2 in next terms (8) then add 4 in next term (10) get 14 then add one more 4 and get 18. next term would be either 24 or may be 26. if you interpret 4 as double of 2 then next term would be 26 cause after 4 it would be 8 to be added, which is double of 4 and if you interpret 4 by adding 2 in 2 then you'll add 2 in 4 which is 6 and hence would add 6 in 18 to get 24)

4. 4 20 35 49 ans 62
(first add 16 then 15 then 14 then 13 then 12 and go on)

5. 6 11 20 37 ans 70
(6*2=12 subtract 1 and get 11. 11*2 get 22 subtract 2 and get 20, 20*2 get 40 and subtract 3 to get answer 37 to carry on 37*2 and get 74 subtract 4 to get answer 70)

6. 1 3 9 27 ans 81
(every term is multiplied by 3 to get next term)

These were the easiest series. There are very difficult series which are hard nuts to crack in the limited time in exam. Be ready for difficult one.

[QUOTE=mashal khan;169791]please somebudy explain these questions.i dont such kind of questions?[/QUOTE]

In these questions, you have to complete the series keeping given members of the series in consideration.

Lets start with
[SIZE=3][COLOR=DarkRed][B]1 3 9 27 ?[/B][/COLOR][/SIZE]

The have given us, first four members of the series and the fifth one is required.

Its quite obvious that it is a series of 3^(n-1) where n is the position of the number in the series.

3^0 = 1 which is the first member of the series
3^1 = 3 which is the second member
3^2 = 9 which is the third member
3^3 = 27 which is the fourth member
[COLOR=Navy][B]3^4 = 81 which is the fifth and the required member[/B][/COLOR]

Now take
[SIZE=3][COLOR=DarkRed][B]6 11 20 37 ?[/B][/COLOR][/SIZE]

6 is the first member of the series
( [B]6[/B] x 2 ) - [B]1[/B] = 12 - 1 = 11 which is the second member
( [B]11[/B] X 2 ) - [B]2[/B] = 22 - 2 = 20 which is the third member
( [B]20[/B] x 2 ) - [B]3[/B] = 40 - 3 = 37 which is the fourth member
[B][COLOR=Navy] ( 37 x 2 ) - 4 = 74 - 4 = 70 which [/COLOR][/B][B][COLOR=Navy]is the fifth and the required member

[/COLOR][/B][COLOR=Navy][COLOR=Black]Now lets move to
[/COLOR][/COLOR][COLOR=DarkRed][B][SIZE=3]4 20 35 49[/SIZE][/B][/COLOR]
[COLOR=Navy][COLOR=Black]
4 is the first member [/COLOR][/COLOR] of the series
[COLOR=Navy][COLOR=Black]4 + [B]16[/B] = 20 which is the second member
20 + [B]15[/B]=35 [/COLOR][/COLOR][COLOR=Navy][COLOR=Black]which is the third member[/COLOR][/COLOR]
[COLOR=Navy][COLOR=Black]35 + [B]14[/B] = 49 [/COLOR][/COLOR][COLOR=Navy][COLOR=Black]which is the foruth member[/COLOR][/COLOR]
[COLOR=Navy][B]49 + 13 = 62 which is the fifth and the required member[/B][/COLOR]
[COLOR=Navy][COLOR=Black]
Now we have
[/COLOR][/COLOR][B][SIZE=3][COLOR=DarkRed]6 8 10 14[/COLOR][/SIZE][/B]

[COLOR=Navy][COLOR=Black]6 is the first member [/COLOR][/COLOR] of the series
[COLOR=Navy][COLOR=Black]6 + [B]2[/B] = 8 which is the second member
8 + [B]2 [/B]= 10 [/COLOR][/COLOR][COLOR=Navy][COLOR=Black]which is the third member[/COLOR][/COLOR]
[COLOR=Navy][COLOR=Black]10 + [B]4[/B] = 14 [/COLOR][/COLOR][COLOR=Navy][COLOR=Black]which is the foruth member[/COLOR][/COLOR]
[COLOR=Navy][B]14 + 4 = 18 which is the fifth and the required member[/B][/COLOR]
[COLOR=Navy][COLOR=Black]
Now
[/COLOR][/COLOR][SIZE=3][COLOR=DarkRed][B]212 179 146 113[/B][/COLOR][/SIZE]

[COLOR=Navy][COLOR=Black]212 is the first member [/COLOR][/COLOR] of the series
[COLOR=Navy][COLOR=Black]212 - [B]33[/B] = 179 which is the second member
179 - [B]33 [/B]= 146 [/COLOR][/COLOR][COLOR=Navy][COLOR=Black]which is the third member[/COLOR][/COLOR]
[COLOR=Navy][COLOR=Black]146 - [B]33[/B] = 113 [/COLOR][/COLOR][COLOR=Navy][COLOR=Black]which is the foruth member[/COLOR][/COLOR]
[COLOR=Navy][B]113 - 33 = 80 which is the fifth and the required member[/B][/COLOR]
[COLOR=Navy][COLOR=Black]
Here is the last one
[/COLOR][/COLOR][SIZE=3][COLOR=DarkRed][B]18 20 24 32[/B][/COLOR][/SIZE]
[COLOR=Navy][COLOR=Black]
18 is the first member [/COLOR][/COLOR] of the series
18 [COLOR=Navy][COLOR=Black]+ (2^1) = 18 + 2 = 20 which is the second member
20 + [/COLOR][/COLOR][COLOR=Navy][COLOR=Black](2^2) = 20 + 4 [/COLOR][/COLOR][COLOR=Navy][COLOR=Black]= 24 [/COLOR][/COLOR][COLOR=Navy][COLOR=Black]which is the third member[/COLOR][/COLOR]
[COLOR=Navy][COLOR=Black]24 + [/COLOR][/COLOR][COLOR=Navy][COLOR=Black](2^3) = 24 + 8 = 32 [/COLOR][/COLOR][COLOR=Navy][COLOR=Black]which is the foruth member[/COLOR][/COLOR]
[COLOR=Navy][B]32 + (2^4) = 32 + 16 = 48 which is the fifth and the required member[/B][/COLOR]
[COLOR=Navy][COLOR=Black]
[/COLOR][/COLOR]In all such series, there is a pattern. One just needs practice to identify it.
[COLOR=Navy][COLOR=Black]
[/COLOR][/COLOR]

AOA


Here is another

[SIZE="4"][B]2,12,30,56,...[/B][/SIZE]

now there is no common difference or any apparent symmetry

If u anlyse then

[B][SIZE="3"]2=1*2,
12=3*4,
30=5*6,
56=7*8[/SIZE][/B]

hence the next member will b [B][SIZE="3"]90=9*10[/SIZE][/B]

If someone wants to do practice then consult ISSB books or Mathematics book of Ist year. very helpful.

Regards

Buddy how can we solve such questions is there any specific rules or basis for such kind of questions?

Such questions have always patterns. they are called series or sequence. for those who know how to solve this they call it common sense. May be you are finding some difficulty otherwise they are very easy with some practice.
You have to find some patterns. some rule on which next term is written and using that pattern you have to find the answer.

like if it is given. 2, 4, 6 the next term will surely be 8.
and if it is. 3, 6, 9 next term would surely be 12. such sequences are a bit more complex than these i told. usually 3 terms need to be given to find the fourth. because two terms cant tell you about any pattern.

As, if it is 3 , 6, here you dont know whats the pattern. whether they doubled 3 to get 6 or simply added 3 in 3. if the doubled 3 then 6 would also be doubled to get 12 and series will be 3, 6,12, 24 and if they added 3 in 3 then it would be. 3,6 ,9,12,15 etc..
So mostly at least 3 terms are given and sometimes 4 if pattern is more complex.

Anyway in short you have to find common pattern in those 3 or 4 given terms. its like finding the relation between the terms.

The relation or pattern which exists between 1st and 2nd term and if the same exists in 2nd and 3rd term then this must exist in 3rd and 4th term.

In 2 terms like 3, 6 you cant find pattern. because it may be a single thing while patterns means repetition of something. If you find that pattern or rule or relation by which first 3 terms are written you are sure to find the fourth term even if the option is not given.

Reference
 

Salam to all member. To know about series just simply consult Mathematics F.Sc Part-I Chapter 6, which help u & u ppl never be skip after study of such chapter. any qurry plz post reply. i'm here to resolve it if i could.

thanks bright...
 

its ok..you just explain the basis of such kind of questions?

[QUOTE=mashal khan;170286]its ok..you just explain the basis of such kind of questions?[/QUOTE]

Actually this type of questions have no certain rule. The rule varies from question to question.

You have to find out the pattern of the series that in which manner the next term related to the previous.

I can only solve the problems if u need.

U may practice these questions from the book of ISSB (Intelligence tests).

Regards