Answer:
cost per unit of gas i.e y= 0.36
Step-by-step explanation:
Let cost per unit of electricity = x
and cost per unit of gas = y
The equations required will be:
[tex]600x+100y=390 ---- eq(1)\\400x+250y=326----eq(2)[/tex]
We need to find value of y i.e cost per unit of gas
Solving equations to find value of y
We will use elimination method
Multiply equation 1 by 4 and 2 by 6
[tex]2400x+400y=1560 ---- eq(1)\\2400x+1500y=1956----eq(2)[/tex]
Subtracting eq 1 from eq 2
[tex]2400x+1500y=1956----eq(2)\\2400x+400y=1560 ---- eq(1)\\- \ \ \ \ \ - \ \ \ \ \ \ \ \ \ \ -\\----------------\\1100y=396\\y=\frac{396}{1100}\\y=0.36[/tex]
Solving we get y=0.36
Putting value of y in eq(1) to find value of x
[tex]600x+100y=390\\600x+100(0.36)=390\\600x+36=390\\600x=390-36\\600x=354\\x=\frac{354}{600}\\x=0.59[/tex]
Value of x = 0.59
But we need to find only cost of unit of gas i.e y
So, cost per unit of gas i,e y= 0.36
