In order to make a stem and leaf plot, each observed value must first be separated into its two parts:
The stem is the first digit or digits;
The leaf is the final digit of a value;
so the graph will be
Steam Leaf
1 3,3,5,7,9
2 0,1
3
4 0,8
5 2,5
6 0
The key on this plot shows that the stem is the tens place and the leaf is the ones place.
the key is 1|3= 13 years old