Logical Reasoning - Number Series - Discussion
Discussion Forum : Number Series - Type 1 (Q.No. 8)
Directions to Solve
In each series, look for the degree and direction of change between the numbers. In other words, do the numbers increase or decrease, and by how much
8.
Look at this series: 3, 4, 7, 8, 11, 12, ... What number should come next?
Answer: Option
Explanation:
This alternating addition series begins with 3; then 1 is added to give 4; then 3 is added to give 7; then 1 is added, and so on.
Discussion:
41 comments Page 4 of 5.
Tukaram Patil said:
1 decade ago
After 3, 4 this alternative 2 nos. are missing i.e(5 & 6).
After 7, 8 this alternative 2 nos. are missing i.e(9 & 10).
After 11, 12 this alternative 2 nos. should miss i.e(13 & 14).
So D ans is 15.
After 7, 8 this alternative 2 nos. are missing i.e(9 & 10).
After 11, 12 this alternative 2 nos. should miss i.e(13 & 14).
So D ans is 15.
Jagani said:
1 decade ago
3+1=4;
4+3=7;
7+1=8;
8+3=11;
11+1=12;
12+3=15;
Logic for add one and three.
4+3=7;
7+1=8;
8+3=11;
11+1=12;
12+3=15;
Logic for add one and three.
Venkatesh Prasad said:
1 decade ago
It is a series of odd numbers.
Were the even place numbers are subtracted by 1.
3, 5, 7, 9, 11, 13, 15
(5-1) (9-1) (13-1)
3, 4, 7, 8, 11, 12, 15
Were the even place numbers are subtracted by 1.
3, 5, 7, 9, 11, 13, 15
(5-1) (9-1) (13-1)
3, 4, 7, 8, 11, 12, 15
Sanju reddy said:
1 decade ago
It can also be done in this way.
4-3=1
7-4=3
8-7=1
11-8=3
12-11=1
15-12=3
Therefore, the difference b/w the two consecutive no's is in the form 1,3,1,3,1 and so on.
4-3=1
7-4=3
8-7=1
11-8=3
12-11=1
15-12=3
Therefore, the difference b/w the two consecutive no's is in the form 1,3,1,3,1 and so on.
Aditya said:
1 decade ago
3+1= 4
4+3= 7
7+1= 8
8+3= 11
11+1= 12
12+3=15
4+3= 7
7+1= 8
8+3= 11
11+1= 12
12+3=15
Ch.shravan kumar said:
1 decade ago
3+1=4;
4+3=7;
7+1=8;
8+3=11;
11+1=12;
12+3=15;
we use 1 and 3 add nos
4+3=7;
7+1=8;
8+3=11;
11+1=12;
12+3=15;
we use 1 and 3 add nos
Pundrik Vinayak said:
1 decade ago
3 7 11 15 19 23....
4 8 12 16 20.........
4 8 12 16 20.........
Nandini said:
1 decade ago
Difference between 3, 7, 11 and 4, 8, 12 is same so the next no is 11+4=15.
Sunita S. said:
1 decade ago
after 3, 4 this alternative 2 nos. r missing i.e(5 & 6)
after 7, 8 this alternative 2 nos. r missing i.e(9 & 10)
after 11, 12 this alternative 2 nos. should miss i.e(13 & 14)
so d ans is 15.
after 7, 8 this alternative 2 nos. r missing i.e(9 & 10)
after 11, 12 this alternative 2 nos. should miss i.e(13 & 14)
so d ans is 15.
Sonal said:
2 decades ago
Good answer.
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