How many hours does it take for a light bulb to use as much electricity as a heater uses in one hour

Hi there

One pound of salmon will cost $13, and one pound of tuna will cost $8.

Here's why.

X will be the cost of pound of salmon, and y will be the cost of a pound of tuna.
| 15x+8y=259
| 12x+6y-204

6y = 204-12x
y=34-2x

15x+8(34-2x)=259
272-259=16x-15x
x=13

y=34-2*13
y=34-26
y=8

So, again...
1lb Salmon : $13
1lb Tuna : $8