# algebra - Help!

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The local fish market is having a sale on whole fish. the prices are as follows:

You can buy an albacore and a barracuda for\$21
You can buy a barracuda and a carp for \$32
You can buy a carp and a dogfish for \$32
You can buy a dogfish and an eel for \$37
You can buy an eel and flounder for \$31
You can buy a flounder and a gar for \$25
You can buy gar and an albacore for \$26

Determine the cost of each individual fish

• See reply to Brandon above -

I gave a method a few minutes ago.

• algebra - Help! -

Price list:
Albacore \$12
Barracuda \$9
Carp \$15
Dogfish \$17
Eel \$20
Flounder \$11
Gar \$14

Proof: Call the fish A-G and make all the prices into simple addition equations.

Add all the numbers and equations together. You get:

2(A+B+C+D+E+F+G) = 196.

And thus,

(A+B+C+D+E+F+G) = 98

After that, add together the first, third, fifth, and seventh equations.

(A+B+C+D+E+F+G+A) = 110

And then subtract the last two equations I've written from each other, leaving...

A = 12.

After that, it's a matter of simple addition i know this is late

• algebra - Help! -

Thank you Unknown Guy, helped a lot!