Please do not delete your questions.
Someone could have been in the process of answering it.
Plus someone else could have learned from that answer.
If you do not need an answer anymore just write a new post saying something like:
"Thanks to all those that look at my question but I do not need an answer any more.
I have worked it our for myself "
oh sorry!! do i post the question again ?
Don't worry about it this time unless someone asks for it.
Just don't do it again :)
Every now again I wll spend a long time answering a question and then when I go to post it the question has been removed, or changed without comment. It can be infuriating.