Question

简便计算 急！

1、456-198 2、45×0.99 3、720÷5÷6 4、3.2×12.5×0.25

Answer 1

1、456-198
=456-(200-2)
=456-200+2
=256+2
=258

2、45×0.99
=45×(1-0.01)
=45×1-45×0.01
=45-0.45
=44.55

3、720÷5÷6
=720÷(5×6)
=720÷30
=24

4、3.2×12.5×0.25
=0.8×4×12.5×0.25
=(0.8×12.5)×(4×0.25)
=10×1
=10

Answer 2

1.456-200+2=256+2=258
2.45*(1-0.01)=45-0.45=44.55
3.720÷(5*6)=720÷30=72÷3=24
4.4*0.8*12.5*0.25=4*0.25*0.8*12.5=10

Answer 3

1.
456-198
=456-200+2
=256+2
=258.

2.
45×0.99
=45*(1-0.01)
=45-0.45
=44.55

3.
720÷5÷6
=720÷6÷5
=120÷(10÷2)
=120÷10*2
=12*2
=24.

4.
3.2×12.5×0.25
=(0.8*4)*12.5*0.25
=(0.8*12.5)*(0.25*4)
=10*1
=10.

Answer 4

1、456-198=456-(200-2)=456-200+2=258
2、45×0.99=45*(1-0.01)=45-0.45=44.55
3、720÷5÷6=720÷(5×6)=720÷30=24
4、3.2×12.5×0.25=4×0.8×12.5×0.25=(4×0.25)×(0.8×12.5)=1×10=10

Answer 5

1. 456-198
=456-(200-2)
=456-200+2
=256+2
=254

2.45*0.99
=1*45-0.01*45
=45-0.45
=44.55

3.720/5/6
=720/(5*6)
=720/30
=24

4.3.2×12.5×0.25
=(4×0.8)×12.5×0.25
=(4×0.25)×(0.8×12.5)
=1×10
=10