Question

直接写出得数 678-297= 2/3+1/4= 1.25*0.7*8= 6.4*3/8= 11/20/0.11= 5除以7+七分之二= 0.2/0.2/0.2= 0.5/2

题目是这样的
直接写出得数
678-297= 2/3+1/4= 1.25*0.7*8= 6.4*3/8= 11/20/0.11=
5除以7+七分之二= 0.2/0.2/0.2= 0.5/2/7=

用简便方法计算(写出简便过程）
6.47-（4/9+5.47）-5/9 8.2*9.2+8*0.82

Answer 1

678-297=481
2/3+1/4=11/12
1.25*0.7*8=7
6.4*3/8=2.4
11/20/0.11= 5
5除以7+七分之二=1
0.2/0.2/0.2=5
0.5/2/7=1/28

6.47-（4/9+5.47）-5/9
=6.47-5.47-4/9-4/9
=1-1
=0

8.2*9.2+8*0.82
=8.2*.92+0.8*8.2
=8.2*（9.2+0.8）
=8.2*10
=82

Answer 2

678-297= 381
2/3+1/4= 11/12
1.25*0.7*8= 7
6.4*3/8= 2.4
11/20/0.11= 5
5除以7+七分之二=1
0.2/0.2/0.2= 0.2
0.5/2=0.25

6.47-（4/9+5.47）-5/9
= 6.47-4/9 -5.47 -5/9
=6.47-5.47 -(4/9 +5/9)
=1-1
=0

8.2*9.2+8*0.82
=0.82*10*9.2 +8*0.82
=0.82*92 +0.82*8
=(92+8)*0.82
=100*0.82
=82

Answer 3

678-297=381 2/3+1/4=11/12 1.25*0.7*8=7 6.4*3/8=2.4 11/20/0.11= 5
5除以7+七分之二= 1 0.2/0.2/0.2=5 0.5/2/7=1/28

6.47-（4/9+5.47）-5/9=6.47-5.47-4/9-5/9=（6.47-5.47）-（4/9+5/9）=1+1=2
8.2*9.2+8*0.82=8.2*9.2+0.8*8.2=8.2*（9.2+0.8）=8.2*10=82

Answer 4

687-297=287-300+3=381 2/3+1/4=8/12+3/12=11/12 1.25*0.7*8=（8+2）*0.7=7
6.4*3/8=6.4/8*3=0.8*3=2.4 11/20/0.11==11/0.11/20=100/20=5
5/（7+2/7）=5/（51/7）=35/51 0.2/0.2/0.2=1/0.2=5 0.5/2/7=0.5/14=1/28

6.47-（4/9+5.47）=6.47-5.47-4/9=1-4/9=5/9
8.2*9.2+8*0.82=8.2*9.2+0.8*8.2=8.2*（9.2+0.8）=8.2*10=82