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 4 of 7.
Sarveshwar said:
6 years ago
8+3=11,
11-21=10
10+3=13.
15-18=3,
18-21=3
3+3=6.
Then 13-6=7.
22+3=25, 25-4 = 21.
22,25,21.
11-21=10
10+3=13.
15-18=3,
18-21=3
3+3=6.
Then 13-6=7.
22+3=25, 25-4 = 21.
22,25,21.
Azhar said:
1 decade ago
Good explained by Sundar.
Swapneswar said:
9 years ago
Good explanation @Sundar.
Sundar said:
1 decade ago
8 11 [21] 15 18 [21] 22 25 [21] 29 32 [21] 36 39 [21] 43 46 [21] ....
Here 3, 4 is added alternatively and [21] injected as given below:
Inital = 8
8 + 3 = 11
********** [21]
11 + 4 = 15
15 + 3 = 18
********** [21]
18 + 4 = 22
22 + 3 = 25 <----- Required Answer
********** [21] <----- Required Answer
25 + 4 = 29
29 + 3 = 32
.........etc
Here 3, 4 is added alternatively and [21] injected as given below:
Inital = 8
8 + 3 = 11
********** [21]
11 + 4 = 15
15 + 3 = 18
********** [21]
18 + 4 = 22
22 + 3 = 25 <----- Required Answer
********** [21] <----- Required Answer
25 + 4 = 29
29 + 3 = 32
.........etc
Siva said:
1 decade ago
What is your confusion boss it is easy to get because hare to first number first 3 is added and then as third number interpolation would come and then what is there before interpolation number that would be added by 4 like this it will be go on.
Sameh said:
1 decade ago
I'm not convinced , if the answer was only 25 it would be ok but 25 21 is confusing..
G.priyanga said:
1 decade ago
I did not get this answer. Please explain it clearly.
Sriharsha said:
1 decade ago
What is interpolation?
Saurabh said:
1 decade ago
Hi,
Random number is 21 and is repeated after two number.
3 is adding to 22 the result is 25 and 21 is repeated again.
Random number is 21 and is repeated after two number.
3 is adding to 22 the result is 25 and 21 is repeated again.
Manas said:
1 decade ago
Kindly explain it elaborately, I could not understand the solution.
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