There is a triangular billboard with a height of 6 decimeters and a bottom of 8.4 decimeters. If you paint 50 grams of paint per square meter on its front, do you know how many grams of paint will be used to finish painting this billboard?
有一块三角形的广告牌，高6分米，底是8.4分米．如果在它的正面每平方米刷油漆50克，你知道刷完这个广告牌要用多少克油漆吗？
<gadget id="calculator">8.4 / 2 / 100</gadget>
<output>0.042</output>

<gadget id="calculator">50 * 6 * 0.042</gadget>
<output>12.6</output>

<result>12.6</result>