Answer:
$0.36
Step-by-step explanation:
Let the cost per unit of electricity = e
Let the cost per unit of gas = g
a homeowner used 600 units of electricity and 100 units of gas for a total cost of 390;
600e + 100g = 390 ----- i
400 units of electricity and 250 units of gas were used for a total cost of $326.
400e + 250g = 326 ----- ii
Now we have two equations, and we solve for g;
600e + 100g = 390 ----- i
400e + 250g = 326 ----- ii
Multiply equation i by 4 and equation ii by 6;
2400e + 400g = 1560 ---- iii
2400e + 1500g = 1956 ---- iv
Subtract equation iii from iv;
1100g = 396
g = [tex]\frac{396}{1100}[/tex] = 0.36
Cost per unit of gas $0.36
