Answer:
C. $16.60
Step-by-step explanation:
Let the cost per pound of salmon be represented by x
The cost per pound of swordfish be represented by y
Melissa buys 2 1/2 pounds of salmon and 1 1/4 pounds of swordfish. She pays a total of $31.25
2.5 × x + 1.25× y = $31.25
2.5x + 1.25y = 31.25
The swordfish costs $0.20 per pound less than the salmon.
y = x - 0.20
Hence, we substitute
2.5x + 1.25y = 31.25
2.5y + 1.25(x - 0.20) = 31.25
2.5y + 1.25x - 0.25 = 31.25
2.5x + 1.25x = 31.25 + 0.25
3.75x = 31.5
x = 31.5/3.75
x = $8.4
The cost per pound of salmon be represented by x = $8.4
y = x - 0.20
y = 8.4 - 0.20
y = $8.2
The cost per pound of swordfish be represented by y = $8.2
The cost of a pound of salmon and sword fish
= $8.4 + $8.2
=$16.60