Question 961657
{{{ .18*60 = 10.8 }}} grams of copper in 18% alloy
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(a)
{{{ 60 + 100 = 160 }}} grams in resulting mixture
(b)
{{{ ( 10.8 + 100 ) / 160 }}}
{{{ 110.8 /160 = .6925 }}}
69.25% of the mixture is copper
check answer:
 100 - 69.25 = 30.75% is NOT copper
{{{ .82*60 = 49.2 }}}
{{{ 49.2 / 160 = .3075 }}}
30.75% is not copper
OK