# I Cannot Understand This?

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I was asked to pick a number out of 380, 220, 99 or 256, to be the next number in the sequence 4,5,5,7,14,17,51,55,_

The pattern I can see is as follows:

55-51 = 4
17-14=3
7-5=2
5-4=1

But I can't figure out how to find the right number... can you help me? Thanks.
1 2
i hope recieving help
my opinion, the answer is 220.
how?
the sequence are 4,5,5,7,14,17,51,55,...
5-4 = 1; 5(no in odd position)*1 = 5 (the number next to it)
7-5= 2; 7(no in odd position)*2 =14 (the number next to it)
17-14= 3; 17(no in odd position)*3 = 51 (the number next to it)
55-51=4;55(no in odd position)*4 = 220 (the answer )

get it?
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faizahmad, i think you are right with220
well done brilliant!!!! Students: We have free audio pronunciation exercises.
4 (+1), 5 (x1), 5 (+2), 7 (x2), 14 (+3), 17 (x3), 51 (+4), 55 (x4), 220
So late at night to think...
5-4=1

5x1=5

7-5=2

7x2=14

17-14=3

3x17=51

55-51=4

55x4=220
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