What is next number in this series? 1, 2, 3, 5, 8, ???

Question

On behalf of Sture Sjöstedt

Answer 1

This is a Fibonacci series. The sum of the previous two digits gives the number. So 13

Answer 2

0+1=1
1+1=2
1+2=3
2+3=5
3+5=8
5+8=13

Answer is 13

Answer 3

Answer is 13.
1+2 = 3
2+3 = 5
3+5 =8
5+8 = 13

Answer 4

1+2=3
2+3=5
3+5=8
5+8=13
next number is 13