Would the size of a main sequence star determine its age?

Question

I'm not sure if a small star in a main sequence means the star is going to live longer than a star thats large can somebody please help me??

Answer 1

Yes. There is a direct relation between a main sequece stars size, colour and expected life span. The bigger and hotter a star is, the shorter it will live.  But you can't tell just from the size how old the star is. Therefore you can't tell how long time it has left to live.

But through spectral analyze you can decide the percentage higher elements that the star contains, and from that you can deduce it's real age.  

Answer 2

Mass is the key to the lifespan of a main sequence star.  More mass = shorter life.  Size, brightness, and temperature are all influenced by mass as well, but basically, if a star on the main sequence has more mass than it's cousin that was "born" at the same time...  sorry to say, the big one is gonna bite the dust first.