﹙7.2×9分之1﹚x-2.4=3.2 8.19×3.1-8.19-10×8.19%
2个回答

﹙7.2×9分之1﹚x-2.4=3.2

0.8x-2.4=3.2

0.8x=3.2+2.4

0.8x=5.6

x=7

8.19×3.1-8.19-10×8.19%

=8.19×3.1-8.19-0.1×8.19

=8.19×(3.1-1-0.1)

=8.19×2

=16.38

4分之1÷﹙3-13分之5-13分之8﹚

=1/4÷[3-(5/13+8/13)]

=1/4÷(3-1)

=1/8

17分之8÷23+23分之1×17分之9+23分之1

=8/(17×23)+9/(17×23)+17/(17×23)

=(8+9+17)/(17×23)

=2/23

﹙4-12分之5÷6分之1﹚÷0.1

=(4-5/12×6)×10

=(4-5/2)×10

=3/2×10

=15

42×﹙3分之2+7分之3﹚

=42×2/3+42×3/7

=28+18

=46

5分之2×﹙x-15﹚=5分之48

x-15=48/5÷(2/5)

x-15=24

x=39