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 1 of 5.
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)
Priya said:
2 years ago
Nice, thanks for explaining the answer.
(13)
Pusam Naveen Kumar said:
2 years ago
Here, the common no is 21 so leave it. And the series is;
9 + 2 = 11,
11 + 2 = 13,
13 + 2 = 15,
So, the answer is 15.
9 + 2 = 11,
11 + 2 = 13,
13 + 2 = 15,
So, the answer is 15.
(49)
Jyoti sanju gunjikar said:
2 years ago
Thanks so much all explain me.
(12)
Kaveri said:
3 years ago
According to my logic;
21 - 12 = 9,
21 - 10 = 11,
21 - 8 = 13,
21 - 6 = 15.
21 - 12 = 9,
21 - 10 = 11,
21 - 8 = 13,
21 - 6 = 15.
(51)
Oliyad olana said:
3 years ago
Good, thanks everyone for explaining.
(11)
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)
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)
Sreenivas said:
6 years ago
@All. According to me,
21 - 12 = 9.
9 + 12 = 21.
21 - 10 = 11.
11 + 10 = 21.
21 - 8 = 13.
13 + 8 = 21.
21 - 6 = 15.
15 + 6 = 21.
21 - 12 = 9.
9 + 12 = 21.
21 - 10 = 11.
11 + 10 = 21.
21 - 8 = 13.
13 + 8 = 21.
21 - 6 = 15.
15 + 6 = 21.
(13)
Bhagyalakshmi dayal said:
7 years ago
@Akhilesh.
Thanks this is the simplest one. Thanks for the explanation.
Thanks this is the simplest one. Thanks for the explanation.
(3)
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