The school conference room is paved with square bricks. If you use 8 square decimeters of square bricks, you need 350 pieces; if you use 10 square decimeters of square bricks, how many pieces do you need?
学校会议室用方砖铺地．用8平方分米的方砖铺，需要350块；如果改用10平方分米的方砖铺，需要多少块．
<gadget id="calculator">8 * 350</gadget>
<output>2_800</output>

<gadget id="calculator">2_800 / 10</gadget>
<output>280</output>

<result>280</result>