Given:

Total sell price =$1750=S

second ring sold $50 more than first ring=first ring sold $50 less than second ring ....(i)

third ring sold $600 less than second ring................................................................................(ii)

Let's sell price of 2nd ring=S2

sell price of 1st ring=S1=(S2-$50)...............................from (i)

sell price of 3rd ring=S3=(S2-$600)............................from(ii)

S1+S2+S3=S

(S2-50)+S2+(S2-600)=1750

simplify formula

we get S2=800

S1=800-50=750

S3=800-600=200

S1+S2+S3=750+800+200

=1750

=S.........................hence proved.

so ans is Morrison received for

1st ring=$750

2nd ring =$800

3rd ring=$200