Fire, one syllable or two? Double, one syllable or two?

Question

After believing for a long time that Fire was 2 syllables (FI err) I had a teacher tell me that if it "rolls off your tongue together" it's just one syllable. Of course it's like 12 years later now, but my wife and I were talking about it and it sparked that old memory. Is fire one syllable? Is double pronounced DUBBLE or DUB-ul? Maybe cause I'm from the north-midwest,

"I heard dere was a big fire by da cabin, doncha know." (2 syllables)

And I learned that when I moved south,

"Y'all heard about that there far 'n the woods? Yeehaw." (1 syllable, maybe less)

Answer 1

the correct answer is:
fire ---> 1 syllable
double ---> 2 syllables

Source: http://www.HowManySyllables.com