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next number in the sequence

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next number in the sequence

by sanju09 » Tue Mar 31, 2009 3:01 am
What is the next number in the sequence 3, 0, 3, 12, 27, 48, 75….?
A• 96
B• 105
C• 108
D• 144
E• 150

[spoiler]OA :roll:[/spoiler]
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by Morgoth » Tue Mar 31, 2009 3:20 am
3 , 0, 3, 12, 27, 48, 75

3*1, 3*0, 3*4, 3*9, 3*16, 3*25

so basically our actual sequence is

1, 0, 1, 4, 9, 16, 25

the difference between each number is increasing by 2, or every odd positive integer


0-1 = -1

1-0 = 1

4-1 = 3

9-4 = 5

16-9 = 7

25-16 = 9


-1, 1, 3, 5, 7, 9 --11

25+11 = 36

36*3 = 108 -----------------OA?
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by sanju09 » Tue Mar 31, 2009 3:35 am
Morgoth wrote:3 , 0, 3, 12, 27, 48, 75

3*1, 3*0, 3*4, 3*9, 3*16, 3*25

so basically our actual sequence is

1, 0, 1, 4, 9, 16, 25

the difference between each number is increasing by 2, or every odd positive integer


0-1 = -1

1-0 = 1

4-1 = 3

9-4 = 5

16-9 = 7

25-16 = 9


-1, 1, 3, 5, 7, 9 --11

25+11 = 36

36*3 = 108 -----------------OA?
This explanation could confuse the minority, but it's karr-act in the end.
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by Mozartain » Tue Mar 31, 2009 4:34 am
Morgoth wrote:3 , 0, 3, 12, 27, 48, 75

3*1, 3*0, 3*1, 3*4, 3*9, 3*16, 3*25

so basically our actual sequence is

1, 0, 1, 4, 9, 16, 25
I want to carry on from here, and I really think you've done a very good job up to this point.

If you look at the sequence 1, 0, 1, 4, 9, 16, 25, you can see they're all perfect squares of -1, 0, 1, 2, 3, 4, 5. So the next one should be 6^2=36

Now it's simple --> 3*36 = 108
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by sanju09 » Wed Feb 17, 2010 4:21 am
oic...oac
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by cat er ina » Wed Feb 17, 2010 1:36 pm
hey guys check this out.

sequence is 0 3 3 12 27 48 75.

find the path: from 3 to 12 it s 9 numbers, from 12 to 27 it's 15 numbers, from 27 to 48 it s 21 numbers, from 48 to 75 it s27 ...notice that the sequence icreases of six 9+6 is 15, 15+ 6 is 21, 21+6 is 27 and so on. so let s add six to 27 and we get 33 so the distance between 75, which is the last number that we know is in the set, is going to be 33, add 33 to 75 and it is 108.. am I right??
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by sanju09 » Wed Feb 17, 2010 11:58 pm
cat er ina wrote:hey guys check this out.

sequence is 0 3 3 12 27 48 75.

find the path: from 3 to 12 it s 9 numbers, from 12 to 27 it's 15 numbers, from 27 to 48 it s 21 numbers, from 48 to 75 it s27 ...notice that the sequence icreases of six 9+6 is 15, 15+ 6 is 21, 21+6 is 27 and so on. so let s add six to 27 and we get 33 so the distance between 75, which is the last number that we know is in the set, is going to be 33, add 33 to 75 and it is 108.. am I right??
it's another great observation
The mind is everything. What you think you become. -Lord Buddha



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