8×15
=4×2×15
=4×30
=120
2.35×24
=2.35×2×12
=4.7×12
=(5-0.3)×12
=5×12-0.3×12
=60-3.6
=56.4
3.840÷12
=0.96×4÷(3×4)
=0.96÷3
=0.32
4.540÷45
错了
是4.545÷45
=(4.5+0.045)÷45
=4.5÷45+0.045÷45
=0.1+0.001
=0.101
8×15
=4×2×15
=4×30
=120
2.35×24
=2.35×2×12
=4.7×12
=(5-0.3)×12
=5×12-0.3×12
=60-3.6
=56.4
3.840÷12
=0.96×4÷(3×4)
=0.96÷3
=0.32
4.540÷45
错了
是4.545÷45
=(4.5+0.045)÷45
=4.5÷45+0.045÷45
=0.1+0.001
=0.101