0.75×25÷0.25 0.51÷7.1-0.02簡算

0.75×25÷0.25 0.51÷7.1-0.02簡算

0.75×25÷0.25=0.25×(3×100÷1)=75
0.51÷7.1-0.02=0.51-0.02×7.1=0.368