Latest IBM Aptitude Question SOLUTION: 1,2,3,5,7,10,13,17,_

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(#M40122480) IBM Logical Reasoning question solve the sequence Keep an EYE

1,2,3,5,7,10,13,17,_

Asked In IBM SANTOSH SAHOO (9 years ago)

Solved Sakshi Dikshit Read Solution (34)

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Sakshi Dikshit  (9 years ago) Best Solution

Ans. 21
The difference between 1 and 2 = 1. And difference between 3 and 2 = 1.
Similarly the difference between 5 and 3 = 2. And the difference between 7 and 5 = 2.
Next the difference between 10 and 7 = 3 and 13 and 10 =3.
And the difference between 17 and 13 = 4. So the next digit after 17 must be at a difference of 4. Thus 17 + 4 = 21.

Is this solution Helpfull? Yes (56) | No (2)  

Vishnu Prasad V  (9 years ago)

ANS IS 21
1+1=2
2+1+3
3+2=5
5+2=7
7+3 =10
10+3=13
13+4=17
17+4=21

Is this solution Helpfull? Yes (17) | No (1)  

Pradip Sana  (9 years ago)

21
+1 +1 +2 +2 +3 +3 +4 +4 etc

Is this solution Helpfull? Yes (4) | No (1)  

uma  (9 years ago)

1st series:1,3,7,13,21,....difference:2,4,6,8...
2nd series:2,5,10,17,26,....difference:3,5,7,9...

Is this solution Helpfull? Yes (3) | No   

bomma shwetha  (9 years ago)

1+1=2
2+1=3
3+2=5
5+2=7
7+3=10
10+3=13
13+4=17
17+4=21

Is this solution Helpfull? Yes (2) | No   

Mahender Solkapally  (9 years ago)

ans is 21
1+1=2
2+1+3
3+2=5
5+2=7
7+3=10
10+3=13
13+4=17
17+4=21

Is this solution Helpfull? Yes (2) | No   

NEHA TRIPATHI  (9 years ago)

21.
Explanation if we break d above series in two sub series i.e
1,3,7,13 i.e
3=2+1
7=4+3
13=6+7
so d next term will be
13+8=21 (multiple of 2).

Is this solution Helpfull? Yes (1) | No (1)  

G VENKATARAMANA  (9 years ago)

19 bcz of prime numbers

Is this solution Helpfull? Yes (1) | No (18)  

mara mounica  (9 years ago)

21, after 1,1+1,2+1,3+2,5+2,7+3,10+3,13+4,17+4=21

Is this solution Helpfull? Yes (1) | No   

Lavanya Rathnam  (9 years ago)

asw=22
(1+2)-0=3
(2+3)-0=5
(3+5)-1=7
(5+7)-2=10
7+10-4=13
10+13-6=17
17+13-8=22

Is this solution Helpfull? Yes (1) | No (3)  

Diptabhas  (7 years ago)

1 and 2 difference = 2 and 3 difference
3 and 5 difference = 5 and 7 difference
7 and 10 difference = 10 and 13 difference
13 and 17 difference = 17 and 21 difference
ans: 21

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uttam kumar  (7 years ago)

1,3,7,13,21(difference between digit is increase by 2)
2,5,10,17(difference between digit is increase by 2)

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Devendra Marghade  (9 years ago)

21
(1+1=2), (2+1=3), (3+2=5), (5+2=7), (7+3=10), (10+3=13), (13+4=17), (17+4=21)

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veena pavani  (9 years ago)

ans is 21.
for the first&second number add 1,for the 3rd&4th number add 2 like that for 17 add 4.

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Kaju Gupta  (9 years ago)

1(0)2(0)3(4)5(6)7(8,9)10(11,12)13(14,15,16)17(18,19,20)21
21 is answer

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Koushik Roy  (9 years ago)

it is alternate series please check carefully 1,3,7,13,,21 because gap b/w 1 to 3 is 2,3 to 7 is 4,7 to 17 is 6 then 13 to 21 is 8 so it must be 21.

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Nagapatla.Rekha  (9 years ago)

their are 2 series in the sequence
1+2=3,3+4=7,7+6=13(add answer with even numbers)
2 +3=5,5+5=10,10+7=17(add answer with odd number)
so the answer is 13+8=21

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shabana banu shaik  (9 years ago)

21...diff b/w 2 and 1 is 1 and 3 and 2 is 1,diff b/w 5 and 3 is 2 in d same way diff b/w 7 and 5 is 2...lyk wise diff b/w 13 and 10 is 3.......diff b/w 21 and 17 is 4

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ankita gupta  (9 years ago)

1+1=2
2+1=3
3+2=5
5+2=7
7+3=10
10+3=13
13+4=17
17+4=21
i.e. 21 is answer

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RAJAN GUPTA  (9 years ago)

2-1=1, 3-2=1
5-3=2, 7-5=2
10-7=3, 13-10=3
17-13=4, so 21-17=4
Answer is 21

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suniyc  (9 years ago)

alternate:1,3,7,13 is diffrence=2+4+6....8=21ans
2,5,10,17 is3,5,7....................

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Jyoti kataria  (9 years ago)

1+1=2,2+1=3,+2=5,+2=7,+3=10,+3=13,+4=17,+4=21
ans is 21

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Asmit Kumar  (9 years ago)

ANS IS 21
1+1=2
2+1+3
3+2=5
5+2=7
7+3 =10
10+3=13
13+4=17
17+4=21

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Lakshmi  (8 years ago)

21
1+1=2+1=3
3+2=5+2=7
7+3=10+3=13
13+4=17+4=21

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roopa  (8 years ago)

find the differences
1-2=1
2-3=1
3-5=2
5-7=2
7-10=3
10-13=3
13-17=4
17-21=4
answer :21

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AARATHI A  (8 years ago)

ans=21
1 2 3 (4) 5 (6) 7 (8)(9) 10 (11)(12) 13 (14)(15)(16) 17 (18)(19)(20) 21
skip all nos in brackets

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pravesh kumar  (8 years ago)

ans is 21

first two is gap 1
next two is 2 gap
and next two again 3
and other next will 4
17+4=21

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MANUPOTI ANAND  (8 years ago)

1+1=2
2+1=3
3+2=5
5+2=7
7+3=10
10+3=13
13+4=17
17+4=21

Is this solution Helpfull? Yes | No (1)  

Ashraf Mohammad  (8 years ago)

21 2-1,3-2 difference 1, 5-3,7-5 difference 2 10-7,13-10 difference 3 17-13,21-17 difference 4

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Samjukta Das  (7 years ago)

It will be 21

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lakshmi prasanna  (6 years ago)

2-1=1
3-2=1
5-3=2
7-5=2
10-7=3
13-10=3
17-13=4
21-17=4

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siri  (6 years ago)

next number in series is 21

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Raj Lakshmi  (6 years ago)

1+1=2
2+1+3
3+2=5
5+2=7
7+3 =10
10+3=13
13+4=17
17+4=21
answer is 21

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Hari Krishna Yadav  (4 years ago)

the difference between 1 and 2 is =1 . and difference between 3 and 2=1
sim,the difference between 5 and 3 is 2. and diff between 7 and 5 is 2
10 and 7 is 3 and 13 and 10=3
diff between 17 and 13=4
after 17 must be at a difference of 4 .then 17+4=21

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