Hello!
To solve this we have to work backwards
When she goes west we add how far she went
When she goes east we subtract how far she went
She was 2km east of Albert's home
This can be +2
To get there she went 4km east
She started 4km to the west which is -4
2 + -4 = -2
She went twice of 1km east
twice of 1 is 2
-2 - 2 = -4
She went 1km west
We do the opposite
-4 + 1 = -3
She started 3km west of Albert's house
Hope this helps!