Question

Luis was hired to make some jewelry for a special occasion. He needs to make the jewelry out of an alloy that is 54%silver and he requires 10 ounces. He has a large amount of 45% silver and also some that is 75% silver. How many ounces of 45% silver and 75% silver does he need?

Answer 1

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Answer:

• 3 ounces of 75%
• 7 ounces of 45%

Step-by-step explanation:

Let x represent the number of ounces of 75% silver needed. Then (10-x) is the number of ounces of 45% silver. The total silver required is ...

  0.75x +0.45(10 -x) = 0.54(10)

  0.30x +4.5 = 5.4

  0.30x = 0.9

  x = 0.9/0.3 = 3 . . . . . ounces of 75% silver

  10-x = 7 . . . . . ounces of 45% silver

Luis needs 7 ounces of 45% silver and 3 ounces of 75% silver.