<PRE><B>Question 435654</B>
Where did the 31 come from? Oh I see you added the dollar amounts of the charges.6,10,15-

Why are you multiplying 50 times x? It says 50 more not 50 times. Plus it is x that is more than z so you have to add to z to get it to equal x.

At least you tried.
Here you go.
x+y+z=540
x=z+50
6x+10y+15z=5320
Solve these equations to get your three values.
x=170
y=250
z=120</PRE>