Logical Reasoning - Number Series - Discussion
Discussion Forum : Number Series - Type 2 (Q.No. 1)
Directions to Solve
Look carefully for the pattern, and then choose which pair of numbers comes next.
1.
28 25 5 21 18 5 14
Answer: Option
Explanation:
This is an alternating subtraction series with the interpolation of a random number, 5, as every third number. In the subtraction series, 3 is subtracted, then 4, then 3, and so on.
Discussion:
128 comments Page 2 of 13.
Sheshadri DB said:
2 years ago
The random number 5 is every third number.
Subtraction series 3,4,3,4,3,4,3,4.
hence
28-3=25 -> 28,25,5.
25-4=21 -> 21.
21-3=18 -> 21,18,5.
18-4=14 ->14.
14-3=11 ->14,11,5.
11,5 is the answer.
28, 25, 5, 21, 18, 5, 14, 11, 5.
Subtraction series 3,4,3,4,3,4,3,4.
hence
28-3=25 -> 28,25,5.
25-4=21 -> 21.
21-3=18 -> 21,18,5.
18-4=14 ->14.
14-3=11 ->14,11,5.
11,5 is the answer.
28, 25, 5, 21, 18, 5, 14, 11, 5.
(39)
Jatadhari sahoo said:
10 years ago
Its very simple question.
5 is common factor 2 number like:
28.....25....(5).
21.....18....(5).
14.....__....(5).
So 28---25 difference between them 3.
21---18.
= 21-18 = 3.
14 ? 11 - ? = 3 11, followed by 5.
Answer is 11.
5 is common factor 2 number like:
28.....25....(5).
21.....18....(5).
14.....__....(5).
So 28---25 difference between them 3.
21---18.
= 21-18 = 3.
14 ? 11 - ? = 3 11, followed by 5.
Answer is 11.
Billa said:
1 week ago
Given sequence.
28 25 5 | 21 18 5 | 14 ? ?
28 − 25 = 3 → 3 + 2 = 5,
21 − 18 = 3 → 3 + 2 = 5,
14 − 11 = 3 → 3 + 2 = 5.
First number − second number = 3.
Then 3 + 2 = 5.
Finally
After 14, the next number must be 11, and then 5.
28 25 5 | 21 18 5 | 14 ? ?
28 − 25 = 3 → 3 + 2 = 5,
21 − 18 = 3 → 3 + 2 = 5,
14 − 11 = 3 → 3 + 2 = 5.
First number − second number = 3.
Then 3 + 2 = 5.
Finally
After 14, the next number must be 11, and then 5.
(3)
Gauravgupta said:
9 years ago
This is wrong way to solve this series.
Right way is here.
28-3=25.
25-4=21.
21-3=18.
18-4=14.
So first we subtract 3 n then 4 according to series we subtract 3 before 4 so.
14-3=11.
And 5 is interpolation.
Right way is here.
28-3=25.
25-4=21.
21-3=18.
18-4=14.
So first we subtract 3 n then 4 according to series we subtract 3 before 4 so.
14-3=11.
And 5 is interpolation.
Archana said:
1 decade ago
Nice logic...
28 25 5 21 18 5 14
28-25=3 then
25-21=4 then
21-18=3 then
18-14=4 then
14-11=3 then answer is 11
One by one step we can minus by 3 and 4
Answer: 28 25 5 21 18 5 14 11 5
28 25 5 21 18 5 14
28-25=3 then
25-21=4 then
21-18=3 then
18-14=4 then
14-11=3 then answer is 11
One by one step we can minus by 3 and 4
Answer: 28 25 5 21 18 5 14 11 5
Veeresh said:
1 decade ago
28 25 5 21 18 5 14
28-25 = 3 then
25-21 = 4 then
21-18 = 3 then
18-14 = 4 then
14-11 = 3 then answer is 11
One by one step we can minus by 3 and 4.
Answer: 28 25 5 21 18 5 14 11 5.
28-25 = 3 then
25-21 = 4 then
21-18 = 3 then
18-14 = 4 then
14-11 = 3 then answer is 11
One by one step we can minus by 3 and 4.
Answer: 28 25 5 21 18 5 14 11 5.
Sandip 5. 4 said:
1 decade ago
Nice logic.
28 25 5 21 18 5 14
28-25=3 then
25-21=4 then
21-18=3 then
18-14=4 then
14-11=3 then answer is 11
One by one step we can minus by 3 and 4
Answer: 28 25 5 21 18 5 14 11 5
28 25 5 21 18 5 14
28-25=3 then
25-21=4 then
21-18=3 then
18-14=4 then
14-11=3 then answer is 11
One by one step we can minus by 3 and 4
Answer: 28 25 5 21 18 5 14 11 5
MAHESH said:
1 decade ago
28-3=25 the answer is 3 after the number is 5 next substact the 21 and 18 the answer is 3 the randomly 5 is comes again we substaract 14-3=11 randomly the 5 comes the answer is A.
Siva Prasad said:
1 decade ago
This is really nice because here 5 is reapeted for every number of 2 numbers so if we get the differene between 2 numbers which are between 5 and 5 we can get the answer easily.
CHAUDHARI SATISH said:
3 weeks ago
5 is random 11 & 5 is right Answer.
28-3 = 25 then 5.
25-4=21 then 5.
21-3= 18 then 5.
18-4= 14.
14-3= 11 then 5.
So, 28 25 5 21 18 5 14 11 5 this series.
28-3 = 25 then 5.
25-4=21 then 5.
21-3= 18 then 5.
18-4= 14.
14-3= 11 then 5.
So, 28 25 5 21 18 5 14 11 5 this series.
(1)
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