While writing a resume , I have come across this question while specifying work experience.
Total Experience of One and Half Years
or
Total Experience of One and Half Year
This may seem duplicate question , but I have read Which is it: "1½ years old" or "1½ year old"? but it was inconclusive when it came to time span referred for any activity.
The most idiomatic way to express this with "experience" would be:
One and a half years' experience.
or, possibly
A year and a half of experience.
Some people may well say "a year and a halfs' experience" but in writing it might cause as much debate as what we are having now and that isn't what you want people looking at your resume to do.
