Aptitude - Odd Man Out and Series - Discussion
Discussion Forum : Odd Man Out and Series - Missing No. (Q.No. 6)
Directions to Solve
Insert the missing number.
6.
11, 13, 17, 19, 23, 29, 31, 37, 41, (....)
Answer: Option
Explanation:
Numbers are all primes. The next prime is 43.
Discussion:
8 comments Page 1 of 1.
Karan said:
9 years ago
The logic that I used to find answer was:
11-17=6.
23-17=6.
31-23=8.
41-31=10.
Hence difference of numbers at odd place are (6, 6, 8, 10).
And when we repeat this with even place numbers.
19-13=6.
29-19=10.
37-29=8.
This implies that the difference between the missing number and 37 should generate 6 in order to make the set of difference similar to odd place diff set of (6, 6, 8, 10).
-37=6.
=>ans=37+6=43.
11-17=6.
23-17=6.
31-23=8.
41-31=10.
Hence difference of numbers at odd place are (6, 6, 8, 10).
And when we repeat this with even place numbers.
19-13=6.
29-19=10.
37-29=8.
This implies that the difference between the missing number and 37 should generate 6 in order to make the set of difference similar to odd place diff set of (6, 6, 8, 10).
-37=6.
=>ans=37+6=43.
Divya said:
10 years ago
Its sequence of prime numbers starting from 11, 13, 17,.....
Amey said:
1 decade ago
When we are seeing any sequence then in which way we should judge next number? Means what are the probability that we should check first like even, odd, prime numbers etc ?
Vignesh said:
1 decade ago
11, 13, 17, 19, 23, 29, 31, 37, 41, 43 all are prime numbers, arranged in sequences.
(1)
Chaithanya said:
1 decade ago
Absolutely it is right.
Priya said:
1 decade ago
I think it is in this order +2, -2, +2, +2, -4, +4, -2, +2. When ever it is increasing by some number decreasing by same number in the next number.
(2)
Murali said:
1 decade ago
@Hafiz
Your Answer is wrong. Because,
13-11=2
17-13=4
19-17=2
23-19=4
29-23=6( Alternative number 2 is not Here)
31-29=2( Alternative number 4 is not here)
37-31=6(Alternative number 2 is not Here)
.....
So The Only Answer is Next Prime is 43.
Your Answer is wrong. Because,
13-11=2
17-13=4
19-17=2
23-19=4
29-23=6( Alternative number 2 is not Here)
31-29=2( Alternative number 4 is not here)
37-31=6(Alternative number 2 is not Here)
.....
So The Only Answer is Next Prime is 43.
(1)
Hafiz said:
1 decade ago
I think that
13-11=2
17-13=4
19-17=2
23-17=4
....
41+2=43
the (2,4) (2,4) (2,4 ) is got repeated.
13-11=2
17-13=4
19-17=2
23-17=4
....
41+2=43
the (2,4) (2,4) (2,4 ) is got repeated.
(1)
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