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.
Annam Kanaka Nishanth said:
8 years ago
11.21-8=3.21
15-11.21=4.21
18.21-15=3.21
22-18.21=4.21
Hence
22+3.21=25 21.
15-11.21=4.21
18.21-15=3.21
22-18.21=4.21
Hence
22+3.21=25 21.
Mehtab said:
8 years ago
There is a mistake in explanation. 21 is repeating as random number while 7 is added to each pair to get the new pair.
Salman khan said:
8 years ago
8 11 21 15 18 21 22 25 21
8 + 3 = 11
21
15 + 3 = 18
21
22 + 3 = 25
22.
8 + 3 = 11
21
15 + 3 = 18
21
22 + 3 = 25
22.
(1)
Maranna T said:
8 years ago
Thanks for all the given explanation friends.
Swapneswar said:
9 years ago
Good explanation @Sundar.
DIVAKAR .U said:
9 years ago
8 11 {21} = The difference is 3.
15 18 {21} = The difference is 3.
22 25 {21} = The difference is 3.
15 18 {21} = The difference is 3.
22 25 {21} = The difference is 3.
K.chandra babu said:
9 years ago
Leaving 21 as a third number.
8 + 3 = 11,
15 + 3 = 18,
22 + 3 = 25 so answer will be 25 21, and also first number difference is 7.
8 + 3 = 11,
15 + 3 = 18,
22 + 3 = 25 so answer will be 25 21, and also first number difference is 7.
Joshua said:
9 years ago
I don't understand. Please help me.
Rama kant said:
9 years ago
8 + 7 = 15,
15 + 7 = 22,
11 + 7 = 18,
18 + 7 = 25,
21 is constant.
Every number add 7 except 21.
15 + 7 = 22,
11 + 7 = 18,
18 + 7 = 25,
21 is constant.
Every number add 7 except 21.
Shridhar said:
9 years ago
@Sundar, good answer but please tell me in a simple way.
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