During the earthquake relief work in Yushu, Aunt Zhang sent 500 kilograms of flour, 8 bags were used to make steamed buns, each bag was 50 kilograms, how many kilograms are left?
在玉树抗震救灾中，张阿姨送来了500千克面粉，做馒头用去8袋，每袋50千克，还剩多少千克？
<gadget id="calculator">50 * 8</gadget>
<output>400</output>

<gadget id="calculator">500 - 400</gadget>
<output>100</output>

<result>100</result>