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:
126 comments Page 1 of 13.
AjayKumar said:
1 decade ago
Take first three number as one set. Then take second three number as another set. Here end number these two set is 5. So just leave. Then you have first set as 28 25.
Second set as 21 18.
Here the difference between First number from first set and first number from second set is 7.
Here third set first number is available as 14, then 18-7=11.
Add 5 as last number. Now answer is 14, 11, 5.
Second set as 21 18.
Here the difference between First number from first set and first number from second set is 7.
Here third set first number is available as 14, then 18-7=11.
Add 5 as last number. Now answer is 14, 11, 5.
(1)
Omkar said:
1 decade ago
That is quite simple.
INTERPOLATION here means simply including the number without logic.
28 25 5 21 18 5 14
Here 5 is used as a median you can say remove the 5's
28 25 (diff 3)
21 18 (diff 3)
14 ? (diff 3)( ?=11)
Then the next number is 5 because of interpolation.
28 (-3) 25 & 5
21 (-3) 18 & 5
14 (-3) 11 & 5
Ans (A) 11 5
INTERPOLATION here means simply including the number without logic.
28 25 5 21 18 5 14
Here 5 is used as a median you can say remove the 5's
28 25 (diff 3)
21 18 (diff 3)
14 ? (diff 3)( ?=11)
Then the next number is 5 because of interpolation.
28 (-3) 25 & 5
21 (-3) 18 & 5
14 (-3) 11 & 5
Ans (A) 11 5
Pritish said:
5 years ago
@Roshinireddy.
So divide the list into a pair of 3 values each.
First, we get 28, 25, 5.
So for this 28-25 = 3 which is our main difference. Now they have put 5 randomly here without any logic.
The second pair is 21, 18, 5.
For this 21 -18 = 3 which is again our main difference and put 5 randomly after this.
So divide the list into a pair of 3 values each.
First, we get 28, 25, 5.
So for this 28-25 = 3 which is our main difference. Now they have put 5 randomly here without any logic.
The second pair is 21, 18, 5.
For this 21 -18 = 3 which is again our main difference and put 5 randomly after this.
Rohit T George said:
1 decade ago
@star007
That is quite simple.
INTERPOLATION here means simply including the number without logic.
28 25 5 21 18 5 14
Here 5 is used as a median you can say remove the 5's
28 25 (diff 3)
21 18 (diff 3)
14 ? (diff 3)( ?=11)
Then the next number is 5 because of interpolation.
That is quite simple.
INTERPOLATION here means simply including the number without logic.
28 25 5 21 18 5 14
Here 5 is used as a median you can say remove the 5's
28 25 (diff 3)
21 18 (diff 3)
14 ? (diff 3)( ?=11)
Then the next number is 5 because of interpolation.
Uma said:
1 decade ago
28-21 = 7.
The first figure subtract from the first second set of figure after 5 and which also applies to the next set of figure. i.e the 1st subtracted from the first of the other set and second from the second.
25-18 = 7.
21-14 = 7.
18-7 = 11.
Then 5 is repeated.
The first figure subtract from the first second set of figure after 5 and which also applies to the next set of figure. i.e the 1st subtracted from the first of the other set and second from the second.
25-18 = 7.
21-14 = 7.
18-7 = 11.
Then 5 is repeated.
Saurav said:
7 years ago
@All.
Look at the series carefully on 3rd postion of series "5" is repeating number and the common difference between 1st postion and 2nd postion number is 3 (.i.e. 28-25=3, 21-18=3 so next number should be 14-3=11), so ans for this question is 11 5.
Look at the series carefully on 3rd postion of series "5" is repeating number and the common difference between 1st postion and 2nd postion number is 3 (.i.e. 28-25=3, 21-18=3 so next number should be 14-3=11), so ans for this question is 11 5.
Ram babu said:
1 decade ago
Divide the given series into 3 sets of 3 no. each then find the diff of 1st two no. You will find that in all the 3 sets the diff 3 is common so obviously in the 4th set also the diff is 3 so see the no. Which will give 14 by adding 3 so that the diff is 3.
Rohit vijay said:
1 decade ago
This can be breakdown in a group series of three number:
First series is 28......21.......14 (diff 7).
Second series is 25.....18.......11 (diff 7).
Third series is interpolation of a random number 5...5..5.
So answer is
28,25,5
21,18,5
14,11,5
. . .
First series is 28......21.......14 (diff 7).
Second series is 25.....18.......11 (diff 7).
Third series is interpolation of a random number 5...5..5.
So answer is
28,25,5
21,18,5
14,11,5
. . .
Rashmi Kumari said:
1 decade ago
Difference of 1st and 4th number in series as 7,7,0 so put the value like that. So the next number in series are 11,5
28-21=7(1st no-4th no)
25-18=7(1st no-4th no)
5-5=0(1st no-4th no)
21-14=7(1st no-4th no)
18-11=7(1st no-4th no)
5-5=0(1st no-4th no)
28-21=7(1st no-4th no)
25-18=7(1st no-4th no)
5-5=0(1st no-4th no)
21-14=7(1st no-4th no)
18-11=7(1st no-4th no)
5-5=0(1st no-4th no)
Saurabh Singh said:
3 years ago
INTERPOLATION here means simply including the number without logic.
28 25 5 21 18 5 14.
Here 5 is used as a median you can say remove the 5's
28 25 (diff 3),
21 18 (diff 3),
14 ? (diff 3)( ?=11).
Then the next number is 5 because of interpolation.
28 25 5 21 18 5 14.
Here 5 is used as a median you can say remove the 5's
28 25 (diff 3),
21 18 (diff 3),
14 ? (diff 3)( ?=11).
Then the next number is 5 because of interpolation.
(34)
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