That would be 1/6. To find this, first, move the decimal two places to the right, and put that number over 100:
16.666.../100
This fraction can then be simplified by dividing both sides by 16.666... to get 1/6.
In reality, the fraction 1/6 simply cannot be expressed as a decimal, but many people just put 0.1666666... because it is a pretty good approximation.
Hope this helps!
~ArchimedesEleven