Question 1199152
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The setup for a formal algebraic solution....<br>
(The cost of 30kg of coffee worth $9 per kg), plus (the cost of x kg of coffee worth $5 per kg), equals the cost of ((30+x) kg of coffee worth $7 per kg):<br>
{{{30(9) + x(5) = (30+x)(7)}}}<br>
Solve using basic algebra....<br>
A quick, informal, common sense solution....<br>
The price per kg of the mixture is exactly halfway between the prices for the two kinds of coffee; that means the numbers of kg of the two kinds of coffee are the same.<br>
ANSWER: 30kg<br>