Let g dollars be the price of gold nuggets, s dollars - the price of silver nuggets and b dollars - the price of bronze nuggets.
1)
- If 1 gold nuggets costs $g, then 14 gold nuggets cost $14g;
- If 1 silver nuggets costs $s, then 20 silver nuggets cost $20s;
- If 1 bronze nuggets costs $b, then 24 bronze nuggets cost $24b.
In total they cost $20, then
14g+20s+24b=20.
2)
- If 1 gold nuggets costs $g, then 20 gold nuggets cost $20g;
- If 1 silver nuggets costs $s, then 15 silver nuggets cost $15s;
- If 1 bronze nuggets costs $b, then 19 bronze nuggets cost $19b.
In total they cost $20, then
20g+15s+19b=20.
3)
- If 1 gold nuggets costs $g, then 30 gold nuggets cost $30g;
- If 1 silver nuggets costs $s, then 5 silver nuggets cost $5s;
- If 1 bronze nuggets costs $b, then 13 bronze nuggets cost $13b.
In total they cost $20, then
30g+5s+13b=20.
The system of equations is
[tex]\left\{\begin{array}{l}14g+20s+24b=20\\20g+15s+19b=20\\30g+5s+13b=20\end{array}\right.[/tex]
Answer: correct equations are 2, 5 and 6