Find the rules and fill in the numbers 10,11,21,32,53, ()
The answer is 85
The first two numbers add up to the third,
For example: 10 + 11 = 22
11+21=32
21+32=53
32+53=85
The answer is 21. Why
The first number multiplied by 2, plus the last number, equals the third number
1*2+1=3
1*2+3=5
3*2+5=11
5*2+11=21~
Find the rule 3 5 11 21 43
Let's use n!
n3=2*n1+n2
n4=2*n2+n3
Nx=2*N(x-2)+N(x-1)