Question 1117368
Lee bought a book for ¥300 and sold it to Wong at a profit of x%. Wong then sold the same book to Fei at a profit of x%.If Fei paid ¥(6x+0.75) more for the book than what Lee paid, find the value of x. 
<pre>These people CLAIM to be TUTORS!! Ha, ha, ha!!!

Since Lee bought the book for  ¥300 and sold it to WONG at a profit of x%, he sold it for: {{{300(1 + x/100)}}}
Since Wong bought the book for {{{300(1 + x/100)}}}, and sold it to FEI at a profit of x%, he sold it for: {{{300(1 + x/100)(1 + x/100)}}}
{{{300(1 + 2(x/100) + (x/100)^2)}}} ======> {{{matrix(1,3, 300(1 + x/50 + x^2/"10,000"), "=", 300 + 6x + 3x^2/100)}}}
Amount Fei paid: {{{300 + 6x + 3x^2/100)}}}              Amount Lee paid: ¥300 
We then get: {{{matrix(1,3, 300 + 6x + 3x^2/100, "=", 300 + 6x + .75)}}}
{{{matrix(1,3, 3x^2/100 + 6x - 6x, "=", 300 - 300 + .75)}}}
{{{matrix(1,3, 3x^2/100, "=", .75)}}}
{{{matrix(1,3, 3x^2, "=", 75)}}} --------- Cross-multiplying
{{{matrix(1,3, x^2, "=", 75/3)}}}
{{{matrix(1,3, x^2, "=", 25)}}}
{{{highlight_green(matrix(1,5, x, "=", sqrt(25), "=", 5))}}}