Question

what are the first 15 counting numbers in base 9

Answer 1

as its base 9 you will have 9 digits 0 -8
you start at 1 of course
- what number comes after 8?

Answer 2

How do you find the first 15 counting numbers

Answer 3

1,2,3,4,5,6,7,8 - then what?

Answer 4

the next number is 10
then 11,12,13,14,15,15

Answer 5

* last one is 16

Answer 6

Slightly different way of approaching this:
\[1_{10}=1(10^0)\\
1_9=1=1(9^0)\]
\[2_{10}=2=2(10^0)\\
2_9=2=2(9^0)\]
...
\[8_{10}=8=8(10^0)\\
8_9=8=8(9^0)\]
\[9_{10}=9=9(10^0)\\
9_9=10=1(9^1)+0(9^0)\]
\[10_{10}=10=1(10^1)+0(10^0)\\
10_9=11=1(9^1)+1(9^0)\]
\[11_{10}=11=1(10^1)+1(10^0)\\
11_9=12=1(9^1)+2(9^0)\]
and so on.