<PRE><B>Question 1099098</B>
let x equal the cost of the product.


390 = x + .20 * x
combine like terms to get 390 = 1.2 * x
divide both sides of this equation by 1.2 to get 390 / 1.2 = x
solve for x to get x = 390 / 1.2 = 325


in essence, you multiplied the cost by 1.2 to get the retail price.
to get back to the cost, you need to divide the retail price by 1.2.


don&#39;t forget that 20% means 20 per 100, therefore 20% can be viewed as 20/100 which is equal to .2
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