wrote:
For the sake of this discussion assume that all things are equal
regarding quality of parts. I have an inexpensive mt bike with the
standard fairly wide tires and am thinking of getting a new
inexpensive 26 in. bike however this one has the very thin tires. The
mt. bike tires appear to be at least three times as wide and possibly
4. Since there is much less friction associated with the thin tires
and remember all things considered equal can I assume that the same
energy and exertion that I put into pedaling the mt. bike will be at
the very least 2 or more times effective when pedaling the bike with
the very thin tires.

Sounds like you're buying the second bike just for the skinny tires?

Do you ride on dirt trails, gravel paths, or pavement?

Horses for courses.

BS (no, really)