Paul needs 40 pounds of 48% silver alloy to finish a collection of jewelry. How many pounds each of 45% silver alloy and 60% silver alloy should he melt together to obtain the alloy he needs

Respuesta :

Equation:
silver + silver = silver
0.45x + 0.60(40-x) = 0.48*40
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45x + 60*40 - 60x = 48*40

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-15x = -12*40
x = (4/5)40
x = 32 lbs (amt of 45% slloy needed)
40-x = 8 lbs (amt of 60% alloy needed)