Logical Reasoning - Number Series - Discussion
Discussion Forum : Number Series - Type 2 (Q.No. 2)
Directions to Solve
Look carefully for the pattern, and then choose which pair of numbers comes next.
2.
8 11 21 15 18 21 22
Answer: Option
Explanation:
This is an alternating addition series, with a random number, 21, interpolated as every third number. The addition series alternates between adding 3 and adding 4. The number 21 appears after each number arrived at by adding 3.
Discussion:
66 comments Page 3 of 7.
Priyanka said:
1 decade ago
SOLUTION:
Here number 21 put as a interpolatn dat means only to confuse you. So just excluding that series will be like as:
8+3=11 (add 3 & interpolation 21)
15+3=18 (add 3 & interpolation 21)
Now 22+3 =25 (add 3 & interpolation 21)
So answer wil be B) 25 21 because 25 final anwer and 21 as a interpolation.
Hope now you get it.
Here number 21 put as a interpolatn dat means only to confuse you. So just excluding that series will be like as:
8+3=11 (add 3 & interpolation 21)
15+3=18 (add 3 & interpolation 21)
Now 22+3 =25 (add 3 & interpolation 21)
So answer wil be B) 25 21 because 25 final anwer and 21 as a interpolation.
Hope now you get it.
Saikanth said:
1 decade ago
8+3 = 11
11+4 = 15
15+3 = 18
18+4 = 22
From above we can conclude as difference b/w first two no.is 3.
Third no. is interpolation, it is repeated as every third no.
so next pair is 25 21 (22+3 =25)
11+4 = 15
15+3 = 18
18+4 = 22
From above we can conclude as difference b/w first two no.is 3.
Third no. is interpolation, it is repeated as every third no.
so next pair is 25 21 (22+3 =25)
Paramjeetkaur said:
1 decade ago
Thanks Sundar.
Saravanan.O said:
1 decade ago
There are two condition is here
1. Every 3rd number is 21
2. Difference between 2 and 1 number is 3.
In this way,
8-11=3
21
15-18=3
21
22-25=3. so the answer is 25 21
1. Every 3rd number is 21
2. Difference between 2 and 1 number is 3.
In this way,
8-11=3
21
15-18=3
21
22-25=3. so the answer is 25 21
Harpreet Singh said:
1 decade ago
21 is common after every 2 number. So
8 11 21 15 18 21 22...
8+3 = 11 21.
15+3 = 18 21.
22+3 = 25 21.
So answer is 25 21.
8 11 21 15 18 21 22...
8+3 = 11 21.
15+3 = 18 21.
22+3 = 25 21.
So answer is 25 21.
Ashish minz said:
1 decade ago
@Harpreet Singh.
How he get 3..
11-8 = 3 21 is fixed.
18-15 = 3.
How he get 3..
11-8 = 3 21 is fixed.
18-15 = 3.
Hasan faraz said:
1 decade ago
Good question.
8 11 21 15 18 21 22
It is a sequence of adding 3, putting 21, adding 4 to the result of adding 3.
8 11 21 15 18 21 22
It is a sequence of adding 3, putting 21, adding 4 to the result of adding 3.
Ashok Bijoy said:
1 decade ago
8(+3) = 11, 21.
15(+3 = 18, 21.
22(+3) = 25, 21.
15(+3 = 18, 21.
22(+3) = 25, 21.
DHARMISHTHa said:
1 decade ago
(8+3)=11 & 21 is common in this series.
(15+3)=18 & 21 is common in this series.
(22+3)=25 & 21 is common in this series.
So, 8, 11, (21), 15, 18, (21), 22, 25, (21),...
(15+3)=18 & 21 is common in this series.
(22+3)=25 & 21 is common in this series.
So, 8, 11, (21), 15, 18, (21), 22, 25, (21),...
Jeyanthi said:
1 decade ago
This type of question is easy but clearly understand the logic.
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