138*11/4+23.3*(2-1/4)-38*1.25+(1+0.25)*28.7(第一个是什么符号)752*1又1/4+4.45*12又1/2+0.035*125=752*1.25+4.45*10*1.25+3.5*1.25=(752+44.5+3.5)*1.25=800*1.25=10007又4480/8333÷21943/25909÷1又18556/35255(分段写清楚)14又2345/2907÷7267/9747*221/4389(加括号,方便辨别)