例:测定含铁样品中w(Fe),比较结果的准确度。 A.铁矿中,T=6238%,x=62.32% E T=-0.06 B.Li2CO3试样中,T=0.042%,x=0.044% x-T=0002 A.E=a×100%=-0.0662.38=-0.1% B.E=-a×100%=0.002/0.042=5% T4 例：测定含铁样品中w(Fe), 比较结果的准确度。 A.铁矿中, T=62.38%, = 62.32% x Ea = x －T= - 0.06% B. Li2CO3试样中, T=0.042%, =0.044% x Ea = x －T=0.002% a r A. 100% E E T =  =－0.06/62.38= - 0.1% a r B. 100% E E T =  =0.002/0.042=5%