`barX_(12)(X_(1)+X_(2)+...+X_(N))/(N_(1)+N_(2))``barX_(12)=(barX_(1)N_(1)+barX_(2)N_(2))/(N_(1)+N_(2))``barX_(12)=(barX_(1)+barX_(2))/(N_(1)+N_(2))`NONE of these
Your experience on this site will be improved by allowing cookies. Read Cookie Policy