Logical Reasoning - Number Series - Discussion
Discussion Forum : Number Series - Type 1 (Q.No. 6)
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
6.
Look at this series: 21, 9, 21, 11, 21, 13, 21, ... What number should come next?
Answer: Option
Explanation:
In this alternating repetition series, the random number 21 is interpolated every other number into an otherwise simple addition series that increases by 2, beginning with the number 9.
Discussion:
45 comments Page 3 of 5.
Sheenam said:
10 years ago
Yes, 11 + 2 = 13.
13 + 2 = 15.
This is very easy question but my according this question is very confused.
13 + 2 = 15.
This is very easy question but my according this question is very confused.
Manoj said:
1 decade ago
21, 9, 21, 11, 21, 13.
21-----after 9, 11, 13.
13-11=2, 11-9=2.
Series on 2.
Then 13+2=15 answer.
21-----after 9, 11, 13.
13-11=2, 11-9=2.
Series on 2.
Then 13+2=15 answer.
Susmita Roy said:
1 year ago
Between the two same number consists of an odd number:
21, 9, 21, 11, 21, 13, 21, 15, 21 and so on.
21, 9, 21, 11, 21, 13, 21, 15, 21 and so on.
(20)
PRAVEEN said:
1 decade ago
21 is the randomly executed and 9, 11, 13 digits are increased by the value 2, so the answer is 15.
Aadesh Rastogi said:
6 years ago
2 * 4 = 8
8 + 1 = 9
2 * 5 = 10
10 + 1 = 11
2 * 6 = 12
12 + 1 = 13
2 * 7 = 14
14 + 1 = 15 and so on.
8 + 1 = 9
2 * 5 = 10
10 + 1 = 11
2 * 6 = 12
12 + 1 = 13
2 * 7 = 14
14 + 1 = 15 and so on.
(9)
Surya said:
1 decade ago
1st, 3rd, 5th, 7th place no's are same
2nd,4h,6th place are adding 2
9+2=11
11+2=13
13+2=15
ans=15
2nd,4h,6th place are adding 2
9+2=11
11+2=13
13+2=15
ans=15
Rupesh Kumar Yadav said:
3 years ago
11-9 = 2.
13-11 = 2.
So, 15-13 = 2.
And next
different will be 2.
9,11,13 Next number will be 15.
13-11 = 2.
So, 15-13 = 2.
And next
different will be 2.
9,11,13 Next number will be 15.
(11)
Saroj said:
1 decade ago
It is done in another way i.e..
by using decreasing order
11-9=2
13-11=2
15-13=2
so decrees the 2
by using decreasing order
11-9=2
13-11=2
15-13=2
so decrees the 2
Boga laxman said:
1 decade ago
21-9 = 12
9-21 = 12
21-11 = 10
11-21 = 10
21-13 = 8
13-21 = 8
21-15 = 6
So answer is 15.
9-21 = 12
21-11 = 10
11-21 = 10
21-13 = 8
13-21 = 8
21-15 = 6
So answer is 15.
Bhargavi said:
1 decade ago
In increasing order by adding +2 then,
9+2 = 11.
11+2 = 13.
13+2 = 15.
So answer is 15.
9+2 = 11.
11+2 = 13.
13+2 = 15.
So answer is 15.
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