能简算的要简算：[2.74-0.56×(2又5/12-1又19/60+2.275)]÷17/20

【2.74-0.56×（29/12-79/60+91/40）】÷17/20
=【2.74-14/25×27/8】÷17/20
=【2.74-1.89】÷17/20
=0.85÷17/20
=0.85÷0.85
=1