The amount y of your friend's allowance if the amount she receives is $4
more than the amount x you receive.
To find the amount y of your friend's allowance if she receives $4 more than the amount x you receive, you need to know the value of x, which represents the amount you receive. Once you know the value of x, you can simply add $4 to find the amount y.
To determine the value of x, you need additional information. If you can provide the value of x, I can calculate the amount y of your friend's allowance.