Logical Reasoning - Number Series - Discussion
Discussion Forum : Number Series - Type 2 (Q.No. 9)
Directions to Solve
Look carefully for the pattern, and then choose which pair of numbers comes next.
9.
21 25 18 29 33 18
Answer: Option
Explanation:
This is a simple addition series with a random number, 18, interpolated as every third number. In the series, 4 is added to each number except 18, to arrive at the next number.
Discussion:
34 comments Page 1 of 4.
Sunny said:
1 decade ago
21 25 18 29 33 18..
In this series we see that 18 is repeated.
So keep 18 aside for some time.
So the series will be - 21, 25, 29, 33.
Now if you look closely the sequence progresses by 4 so in other words it is - 21+4 = 25, 25+4 = 29, 29+4 = 33.
So the next two numbers are 33+4 = 37 and 37+4 = 41.
(IMPORTANT: If in case they wanted the third number then it would have been 18 and not 45 as 18 is repeated after every 2 numbers.)
In this series we see that 18 is repeated.
So keep 18 aside for some time.
So the series will be - 21, 25, 29, 33.
Now if you look closely the sequence progresses by 4 so in other words it is - 21+4 = 25, 25+4 = 29, 29+4 = 33.
So the next two numbers are 33+4 = 37 and 37+4 = 41.
(IMPORTANT: If in case they wanted the third number then it would have been 18 and not 45 as 18 is repeated after every 2 numbers.)
Amit singh Rajput said:
5 years ago
Here, 21,25,18,29,33,18.
.
18 is interpolated as every third number,so the changed numbers should be after 18
21+4 = 25.
25+4 = 29.
29+4 = 33.
33+4 = 37.
37+4 = 41.
Therefore, the answer is 37 41.
Alternative
21,25,18,29,33,18,37,41,18 after 41 again 18 will come.
so according to series 37,41 is correct answer.
.
18 is interpolated as every third number,so the changed numbers should be after 18
21+4 = 25.
25+4 = 29.
29+4 = 33.
33+4 = 37.
37+4 = 41.
Therefore, the answer is 37 41.
Alternative
21,25,18,29,33,18,37,41,18 after 41 again 18 will come.
so according to series 37,41 is correct answer.
(1)
Amit Kumar said:
6 years ago
21, 25,18,29,33,18.
25 - 21 = 4.
keep 18 as that is;
33 - 29 = 4.
again keep 18 as that is;
now , let the next number is X.
then X - 33 = 4.
so , X = 37.
And next term will be X + 4 = 37 + 4 = 41.
18 is repeating after 2 step . so next term will be 18.
Series = 21 , 25 , 18 ,29 ,33, 18 , 37 ,41 , 18.
25 - 21 = 4.
keep 18 as that is;
33 - 29 = 4.
again keep 18 as that is;
now , let the next number is X.
then X - 33 = 4.
so , X = 37.
And next term will be X + 4 = 37 + 4 = 41.
18 is repeating after 2 step . so next term will be 18.
Series = 21 , 25 , 18 ,29 ,33, 18 , 37 ,41 , 18.
Dhiraj Bansal said:
1 decade ago
21 25 18 29 33 18...
In this series we see that 18 is repeated.
So keep 18 aside for some time.
So now series is : 21 25 29 33...
As we are observing difference of 4.
So now the next number is 37.
21 25 18 29 33 18 37 41 18...
So the correct answer is D: 37 41.
In this series we see that 18 is repeated.
So keep 18 aside for some time.
So now series is : 21 25 29 33...
As we are observing difference of 4.
So now the next number is 37.
21 25 18 29 33 18 37 41 18...
So the correct answer is D: 37 41.
Sumit said:
1 year ago
As per the Question, we see here that the 18 comes after every 3rd number.
And considering it we come across the logic that all the numbers have the difference of the (4).
So, option C will be the correct option to choose, as it holds the required value 37, 18.
And considering it we come across the logic that all the numbers have the difference of the (4).
So, option C will be the correct option to choose, as it holds the required value 37, 18.
(5)
Sarmistha said:
1 decade ago
21+18=39 39-10=29
25+18=43 43-10=33
18 is interpolated as every third number,so the changed numbers should be after 18
the series 21 25 18 29 33 18
now, 29+18=47 47-10=37
33+18=51 51-10=41 so the next numbers -- 37 41
series -- 21 25 18 29 33 18 37 41
25+18=43 43-10=33
18 is interpolated as every third number,so the changed numbers should be after 18
the series 21 25 18 29 33 18
now, 29+18=47 47-10=37
33+18=51 51-10=41 so the next numbers -- 37 41
series -- 21 25 18 29 33 18 37 41
HEMA URS said:
1 decade ago
21+4=25 (21,25)
SKIP 18
25+4=29 (25,18,29)
29+4=33 (29,33)
SKIP 18
33+4=37 (33,18,37)
37+4=41 (37,41)
SKIP 18
41+4=45 (41,18,45)
45+4=49 (45,49)
SKIP 18 N SO ON
SO THE FINAL SERIES WILL BE 21,25,18,29,33,18,37,41,18........
SO THE ANSWER IS 37,41
SKIP 18
25+4=29 (25,18,29)
29+4=33 (29,33)
SKIP 18
33+4=37 (33,18,37)
37+4=41 (37,41)
SKIP 18
41+4=45 (41,18,45)
45+4=49 (45,49)
SKIP 18 N SO ON
SO THE FINAL SERIES WILL BE 21,25,18,29,33,18,37,41,18........
SO THE ANSWER IS 37,41
Namratha nayak said:
1 decade ago
In the above series 18 is interpolated as 3rd number. ie., after 21 25 and 29 33.
4 is added to each number to get teh next number. Ie., 21+4=25 (21 25)
25+4=29
29+4=33 (29 33)
Add 4 to 33
33+4=37
37+4=41 (37 41)
I hope this is clear!
4 is added to each number to get teh next number. Ie., 21+4=25 (21 25)
25+4=29
29+4=33 (29 33)
Add 4 to 33
33+4=37
37+4=41 (37 41)
I hope this is clear!
Ghoshi said:
9 months ago
@All.
Many one proposed that option "c" is correct.
But the Right Answer is option "d".
Because 18 comes after two numbers that is "37" & "41".
And the ultimate series is 21, 25, 18, 29, 33, 18, 37, 41, 18.
Many one proposed that option "c" is correct.
But the Right Answer is option "d".
Because 18 comes after two numbers that is "37" & "41".
And the ultimate series is 21, 25, 18, 29, 33, 18, 37, 41, 18.
(6)
Jain said:
9 years ago
"(21) (21+4) 18 (25+4) (29+4) 18 (33+4) (37+4) 18 " where they gave up to 2 and 18. So in b/w 2nd and 3rd 18 two numbers are there. So after 37 & 41 will be the repeated number 18.
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