Question

Melissa buys 212 pounds of salmon and 114 pounds of swordfish. She pays a total of $31.25, and the swordfish costs $0.20 per pound less than the salmon. What would be the combined cost of 1 pound of salmon and 1 pound of swordfish? A. $15.60 B. $15.80 C. $16.60 D. $16.80

Answer 1

C. $16.60

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