2.5+2.5÷0.5-0.5×3
=2.5+5-1.5
=7.5-1.5
=6
(1.5+1.5×3)÷0.6+0.4
=6÷0.6+0.4
=10+0.4
=10.4
10.6-(8.4×0.6-0.54)÷0.9
=10.6-(5.04-0.54)÷0.9
=10.6-4.5÷0.9
=10.4-5
=5.4
24-【22.7-(9.82-2.02)】
=24-【22.7-7.8】
=24-14.9
=9.1
【(17-4.5)×0.2+7.5】×0.31
=【12.5×0.2+7.5】×0.31
=【2.5+7.5】×0.31
=10×0.31
=3.1