Find the next number in this sequence:
$4,3,7,5,10,15,?$
Think outside the frustum here.
Hint 1:
This has to do with a ratio that is of a kind that Pythagoras and his followers didn’t like.
Hint 2:
The title is double the key to the puzzle.
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Sign up to join this communityFind the next number in this sequence:
$4,3,7,5,10,15,?$
Think outside the frustum here.
Hint 1:
This has to do with a ratio that is of a kind that Pythagoras and his followers didn’t like.
Hint 2:
The title is double the key to the puzzle.
Is the answer:
9? Using Hint 2, the key to the puzzle is $\pi$ since $(\dfrac{1}{2} * 6.28 = 3.14)$. Comparing the differences between the nth digit of the sequence and the nth digit of pi results in the natural numbers $1,2,3,...$. As such, the next digit is the 7th digit of $\pi$ plus 7, which is $2+7=9$.
This may be too obvious, but a possible answer is:
6
Reasoning:
Given that 4+3=7 and 5+10=15, the sequence can be interpreted in the form of advancing triplets of the form a+b=c. Since a in each triplet goes up by one, that gives 6 as the next value.
Is it:
13. 4,x,7,x,10,x,13? Just a thought!
Possible solution. I do not have very much basis to give this answer, but I thought I would throw it out there.
Sorry if this is incorrect.
Given that the series is 4,3,7,5,10,15,?, And 4+3=7, 7+5-2=10, Would the next item be 10+15-4=21?
I thought this was too obvious but I don't know.
How about 12? Both the addition and subtraction seem to go up. 4-1, 7-2. 3+4, 5+5, 10+5. I was thinking that the amount of addition was going up by one each time. So, as if it was going: Take once, Add once, Take once, Add twice, take once. The next digit would then be 18, if I'm right?