let b represent the third card
let (b+20) represent the second card
let (2b+20) represent the first card
(2b+20)+(b+20)+b=160
4b+40=160
4b=160-40
4b=120
4b/4=120/4
b=30
2b+20
= 2(30)+20
= 60+20
= 80
b+20
= 30=20
= 60
Therefore, the first card was $80, the second card was $50 and the third card was $30.
