5年级简便计算

(1)2.33*0.5*0.4*5=2.33*5*0.2=2.33*1=2.33
(2)6.9*9.9=6.9*(10-0.1)=69-0.69=68.31
(3)16*7.8*1.25=2*7.8*8*1.25=15.6*10=156
(4)(5.28+5.28+5.28+5.28)*0.25=5.28*4*0.25=5.28
(5)3.69/(1.23*5)=1.23*3/(1.23*5)=3/5=0.6
(6)2.87/0.25=2.87*4=2.5*4+0.37*4=10+1.48=11.48

(1)2.33*0.5*0.4*5
=2.33*(0.5*4*5)
=2.33*(2*5)
=2.33*10
=23.3

(2)6.9*9.9
=6.9*(10-0.1)
=6.9*10-6.9*0.1
=69-0.69
=68.31

(3)16*7.8*1.25
=2*8*7.8*1.25
=(2*7.8)*(8*1.25)
=15.6*10
=156

(4)(5.28+5.28+5.28+5.28)*0.25
=4*5.28*0.25
=5.28*(4*0.25)
=5.28*1
=5.28

(5)3.69/(1.23*5)
=(3.69/1.23)/5
=3/5
=0.6

(6)2.87/0.25
=(2.87*4)/(0.25*4)
=11.48/1
=11.48

1,2.33
2,68.31
3,156
4,5.28
5,0.6
6,11.48

(1)2.33*(0.5*0.4)*5=2.33*(0.2*5)=2.33*1=2.33
(2)6.9*(10-0.1)=69-0.69=68.31
(3)(16*1.25)*7.8=156
(4)5.28*(4*0