Need badly. joe has $6 more than ria and ria has $15 more than eric. together they have $60. how much money does each have? does anyone have the answer, it's driving me crazy

Let the money of ria be r , money of joe be y , money of eric be z
Now,   y=r+6
           z=r-15
Now , the total money is = 60
Then,  r+6 +r + r-15 = 60 (since r+y+z = 60)
3r-9=60
3r=69
r=23
then money: Joe has=23+6=29$
money eric has = 23-15 = 8$
money ria has = 23

21 is the answer the answer is 21