To solve this problem you must apply the proccedure shown below:
1. You have that:
- He sales 13 gold rings and 18 silver rings in 9405 euros.
- The cost of the silver ring is three times the cost of the gold ring.
2. Keeping the information above on mind, you have the following system of equations:
x: the gold ring.
y: the silver ring.
x+y=9405
x=3y
3. Then, you have:
(3y)+y=9405
y=9405/4
y=2351.23 euros
x=3y
x=3(2351.23)
x=7053.75 euros
The answer is:
- Gold ring=7053.75 euros
- Silver ring=2351.23 euros
