# algebra

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a jeweler purchased 5 oz of a gold alloy and 20 oz of a silver alloy for a total cost of \$540. The next day at the same price per ounce, the jeweler purchased 4 oz of th egold alloy and 25 oz of the silver alloy for a total cost of \$450. Find the cost per ounce of the gold and silver alloys.

• algebra -

cost of gold per ounce = x
cost of silver per ounce = y

5x + 20y = 540 ---> x + 4y = 108
4x + 25y = 450

1st equation times 4
4x + 16y = 432
4x + 25y = 450
subtract them
9y = 18
y = 2
sub into x+4y = 108
x + 8 = 108
x = 100

WOW! \$100 per ounce of gold
Quickly tell me where and I will be a millionaire within a few hours, lol

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