Question

未知数.x-5=10 x-60%x=18 40%x+30=80

Answer 1

x-5=10

x=10+5

x=15

x-60%x=18

0.4x=18

x=18÷0.4

x=45

40%x+30=80

0.4x=80-30

0.4x=50

x=50÷0.4

x=125