Lefu Supermarket held an annual profit sharing activity, a single item: 350 yuan for a purchase of 800 yuan; 200 yuan for a purchase of 500 yuan; 50 yuan for a purchase of 200 yuan. If you do not participate in the event, you will be given a 30% discount. Uncle Li bought one commodity worth 900 yuan, 600 yuan and 300 yuan each. How much is the minimum cost?
乐福超市举行周年让利活动，单件商品：满800元减350元；满500减200元；满200元减50元．若不参加活动则一律打7折．李叔叔买了价值900元，600元和300元的商品各一件，最少需要多少元？
<gadget id="calculator">900 - 350</gadget>
<output>550</output>

<gadget id="calculator">600 - 200</gadget>
<output>400</output>

<gadget id="calculator">300 - 50</gadget>
<output>250</output>

<gadget id="calculator">550 + 400 + 250</gadget>
<output>1_200</output>

<result>1_200</result>