(53.76-17.6)÷1.8
=36.16÷1.8
=20又4/45
(0.8×7+4.56÷1.9)×12.5
=0.8*12.5*7+2.4*12.5
=0.8*12.5*7+0.8*12.5*3
=10*(7+3)
=100
15.73-(2.17+0.73)-1.83
=15.73-0.73-(2.17+1.83)
=15-4
=11
(53.76-17.6)÷1.8
=(54-18-0.24+0.4)÷1.8
=30-10+0.16÷1.8
=20又4/45
(0.8×7+4.56÷1.9)×12.5
=(0.8×7+0.8×5.7÷1.9)×12.5
=(0.8×7+0.8×3)×12.5
=0.8×10×12.5
=10×10
=100
15.73-(2.17+0.73)-1.83
=15.73-2.17-0.73-1.83
=15.73-0.73-(2.17+1.83)
=15-4
=11