1. The problem statement, all variables and given/known data The lifetime of the sun on the main sequenceof the hertzprung-russel diagram is estimated to be 10^10 years. Assuming that the luminosities of stars on the upper diagram main sequence vary as mass^4, estimate the solar mass of a star for which it's main squence lifetime is 10^6 years. 2. Relevant equations L = k M^b T = kM / L = k M^1-b T = k M^-2 '=k' is a subsitute for the proportional symbol b = beta 3. The attempt at a solution I know the star is going to be heavier, but I'm not given any values for luminosity. And when I try to equate time to mass I get funny answers. A push in the right direction here?