A batch of goods is priced at an expected profit rate of 50%, but only 70% of the goods are sold. In order to sell the remaining products as soon as possible, the products are decided to be sold at a discounted price, so that the total profit obtained is 82% of the original expected profit. How much discount is the product sold for?
一批商品按50%的期望利润率定价，结果只卖了70%的商品．为尽快卖完剩下的商品，商品决定按定价打折出售，这样所获的全部利润是原来期望获得利润的82%，问商品打了几折出售？
<result>8</result>