Question

What can be concluded about the initial mass of a blue main sequence star compared to a red main sequence star?

Answer 1

mass of blue main sequence star is more than the red main sequence star.

Answer 2

Much larger. Blue versus red implies much higher temperature, since Wien's Law tells you a higher peak frequency of radiation implies a higher temperature. Higher temperature implies both a larger rate of fusion and a lower surface-to-volume ratio (which means a higher temperature is needed for thermal equilibrium, to radiate energy generated by the entire volume out the smaller surface). Both of these imply a larger mass.