number sequence
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number sequence
Hi
Pls help for this question
What are the next two numbers of this squence?
1, 1, 2, 4, 6, 12, 15, ____, _____
(a) 33, 31
(b) 16, 31
(c) 33, 16
(d) 16, 33
Thanks
Rds
Uma
Pls help for this question
What are the next two numbers of this squence?
1, 1, 2, 4, 6, 12, 15, ____, _____
(a) 33, 31
(b) 16, 31
(c) 33, 16
(d) 16, 33
Thanks
Rds
Uma
me too Yoyo!
My colleague and I were trying to work it out earlier for over an hour!!!
I thought at one point that I had got the answer but then when I tried to explain it to my colleague I couldn't get it to come right. The way I worked it out was very complicated!!
I will wait for someone with superior knowledge to me to give the correct answer.
My colleague and I were trying to work it out earlier for over an hour!!!
I thought at one point that I had got the answer but then when I tried to explain it to my colleague I couldn't get it to come right. The way I worked it out was very complicated!!
I will wait for someone with superior knowledge to me to give the correct answer.
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- Posts: 162
- Joined: Sat Jan 12, 2008 7:14 pm
This has been baffling me too!
I split the sequence into 2 alternating ones
ie 1,2,6,15
and 1,4,12
I think that the first sequence is increasing by the square numbers
ie +1, then +4 then +9 so I would expect it then to increase by +16 making the next term in that sequence to be 31 but I can't see a pattern for the second sequence.
Really hoping someone will shed light soon!
CN
I split the sequence into 2 alternating ones
ie 1,2,6,15
and 1,4,12
I think that the first sequence is increasing by the square numbers
ie +1, then +4 then +9 so I would expect it then to increase by +16 making the next term in that sequence to be 31 but I can't see a pattern for the second sequence.
Really hoping someone will shed light soon!
CN
1, 1, 2, 4, 6, 12, 15, ____, _____Complete Novice wrote:This has been baffling me too!
I split the sequence into 2 alternating ones
ie 1,2,6,15
and 1,4,12
I think that the first sequence is increasing by the square numbers
ie +1, then +4 then +9 so I would expect it then to increase by +16 making the next term in that sequence to be 31 but I can't see a pattern for the second sequence.
Really hoping someone will shed light soon!
CN
The second sequence takes the sum of the 3 numbers before including both sequences ie 4 = 2+1+1, 12= 6+4+2, so the final number must equal 15+12+6 & so is 33
- so the answer is A
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- Posts: 1806
- Joined: Mon Feb 20, 2006 2:29 pm
- Location: Berkshire
Re: number sequence
Between DS1 and me, we deduced that;Uma wrote:Hi
Pls help for this question
What are the next two numbers of this squence?
1, 1, 2, 4, 6, 12, 15, ____, _____
(a) 33, 31
(b) 16, 31
(c) 33, 16
(d) 16, 33
Thanks
Rds
Uma
Sequence 1 goes up in Square numbers...
1, 2, 6, 15, 31 difference between each = 1, 4, 9, 16 (All Square numbers)
1, 1, 2, 4, 6, 12, 15, ____, _____
The sum of two consecutive numbers in the first sequence adds up to the difference of the two consecutive numbers in the second sequence.
1+2 = 3 difference between 1 and 4=3
2+6 = 8 difference between 4 and 12=8
6+15 =21 difference between 12 and 33=21
therefore answer is (a) 33, 31
BW