Question 1058432
<pre><b>
{{{matrix(1,7,
(matrix(4,1,Percent,increase,or,decrease)),
"",
""="",
"",
matrix(1,4,Dollar,increase,or,decrease)/matrix(1,2,Original,cost),
""*"",
"100%"
)}}}

Let x = Original cost,

{{{matrix(1,7,
"15%",
"",
""="",
"",
"$30"/x,
""*"",
"100%")}}}

Multiply both sides by x

{{{matrix(1,7,
"15%"*x,
"",
""="",
"",
"$30",
""*"",
"100%")}}}

Drop the percent signs:

{{{matrix(1,7,
15*x,
"",
""="",
"",
"$30",
""*"",
100)}}}

{{{matrix(1,5,
15x,
"",
""="",
"",
"$3000"
)}}}

{{{matrix(1,5,
(15x)/15,
"",
""="",
"",
"$3000"/15
)}}}

{{{matrix(1,5,
x,
"",
""="",
"",
"$200"
)}}}

Edwin</pre></b>