you did south, north, correctly
but last one
twice north is 2 times (x+48) or 2x+96
so
s=x
n=x+48
c=4x
s+c>2x+96
subsitute s for x and 4x for c
x+4x>2x+96
5x>2x+96
minus 2x both sides
3x>96
divide both sides by 3
x>32
it cannot be equal to 32 so
the minimum value is 33 spaces in south car park