A clothing manufacturer has some pure silk thread and some t

A clothing manufacturer has some pure silk thread and some thread that is 85% silk. How many kilograms of each must be woven together to make 75kg. of a blend that is 96% silk?

Solution

85% thread DATA:
Amt. of thread = x kg ; Amt of silk in it= 0.85x kg
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Pure silk DATA:
Amt of thread = \"75-x\"kg ; Amt of silk in it = 1(75-x)kg
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Mixture DATA:
Amt of mixture = 75 kg ; Amt of silk in it = 0.96*75 = 72 kg
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EQUATION:
silk + silk = silk
0.85x + 75-x = 72
-0.15x = -3
x = 20 kg (Amt of 85% thread in the mixture)
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75-x = 55 kg (Amt of pure silk in the mixture)