Question 552163
How many pounds of gourmet candy selling for $2.80 per pound should be mixed with 7 pounds of gourmet candy selling for $1.60 per pound to obtain a mixture selling for $1.96 per pound?
<pre>
{{{(matrix(13,1,x, pounds, of, candy, selling, for, "$2.80", per, pound, which, is, worth, "$2.80"x))}}} + {{{(matrix(15,1,7, pounds, of, candy, selling, for, "$1.60", per, pound, which, is, worth, "$1.60"7,or,"11.20"))}}} = {{{(matrix(13,1,x+7, pounds, of, candy, selling, for, "$1.96", per, pound, which, is, worth, "$1.96"(x+7)))}}}
     &#8595;      &#8595;       &#8595;      &#8595;       &#8595; 
     &#8595;      &#8595;       &#8595;      &#8595;       &#8595;
  $2.80x    +    $11.20    =   $1.96(x+7)

Drop the dollar marks and move the decimals two places right

               280x + 1120 = 196(x+7)

               280x + 1120 = 196x + 1372

Subtract 1120 from both sides:

                      280x = 196x + 252

Subtract 196x from both sides:

                       84x = 252

Divide both sides by 84

                      {{{(84x)/84}}} = {{{252/84}}}
                          
                        x = 3

Answer 3 pounds.

Edwin</pre>