Tìm x biết: x/5 = 2/3

Tìm x biết
a) x/5 = 2/3
b) x/3 - 1/2 = 1/5
c) x/5 + 1/2 = 6/10
d) x+3/15 = 1/3
e) x-12/4 = 1/2
g) 4/5 + x =2/3