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one number in the sequence is wrong find the number 2,3,5,8,13,20,7,18?
23 Answers
- PSU840Lv 61 decade agoFavorite Answer
7...
should be 20, 31, 44.
Every addition is the next highest prime number.
2+1=3
3+2=5
5+3=8
8+5=13
13+7=20
20+11=31
31+13=44
- 1 decade ago
Well I would say 20 is the first wrong number if you start from 1 - 1+2=3 3+5=8 8+13=21 then 1+3+2+1=7 and I am at a loss at how you got to 18
- 1 decade ago
I say 20 is incorrect but the following 7 and 18 have really thrown me out, 2+3 = 5 3+5= 8 5+8=13 8+13=21 so 20 is wrong but cant explain the 7 and 18 i think this is a trick question....
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- Anonymous1 decade ago
It's a Fibonacci series 2+3 + 5, 3+5 +8, 5+8 = 13,
8+13 =21 (not 20) 7 and 18 are also wrong they should be
34 and 55.
- Anonymous1 decade ago
Correct sequence is 2,3,5,8,13,20,31,18.
ie 7 should be 31
The difference between the numbers in the sequence are increasing prime numbers. Assuming 18 is correct then 7 is wrong!
1,2,3,5,7,11,13. Simple init!
