3/8x=225
x=225÷3/8
x=600
x÷2/3=2/5×20
x=8×2/3
x=16/3
x-1/5x=60
4/5x=60
x=60÷4/5
x=75
1/2x÷1/5=10
1/2x=10×1/5
x=2÷1/2
x=4