0.25*32*1.25
=0.25*4*8*1.25
=1*10
=10
7.2/0.5/0.72
=7.2/0.72/0.5
=10/0.5
=20
10.8*9.9
=10.8*(10-0.1)
=10.8*10-10.8*0.1
=108-1.08
=106.92