1/2, 1/4, 1/3, 1/6, 1/5, ?
Look at the sequence of denominators:
2, 4, 3, 6, 5, ?
The 4 is twice 2.
The 3 is is 1 less than the 4
The 6 is twice 3.
The 5 is 1 less than the 6.
Do you see the pattern for the denominators?
The nest denominator will be twice 5, or 10.
Therefore the next term is 1/10,
[The one after that is 1/9, and the one after that is 1/18, etc.]
Edwin