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:
38 comments Page 4 of 4.
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:
1 decade ago
Good answer.
Rajesh Pradhan said:
1 decade ago
This is a very good question.
There is an alternative method for solving this problem.
IE, digit at even & odd places are changes simultaneously.
IE, digit at odd place:- 3+4=7, 7+4=11, 11+4=15 and so on.
& digit at even place:- 4+4=8, 8+4=12 and so on.
Thus here, the answer is 11+4=15.
There is an alternative method for solving this problem.
IE, digit at even & odd places are changes simultaneously.
IE, digit at odd place:- 3+4=7, 7+4=11, 11+4=15 and so on.
& digit at even place:- 4+4=8, 8+4=12 and so on.
Thus here, the answer is 11+4=15.
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