Xiaoming’s house needs to paint a room with a length of 6 meters, a width of 4 meters and a height of 2.5 meters. The doors and windows are 5 square meters without painting. If 2.8 kilograms of Shuangfei powder is used per square meter, how many kilograms of Shuangfei powder will be used to paint the inside of this house?
小明家要粉刷一间长6米，宽4米，高2.5米的房间，门窗一共5平方米不粉刷，如果每平方米用2.8千克双飞粉，粉刷这间房屋的里面要多少千克双飞粉？
<gadget id="calculator">6 * 4</gadget>
<output>24</output>

<gadget id="calculator">6 * 2.5 * 2</gadget>
<output>30</output>

<gadget id="calculator">4 * 2.5 * 2</gadget>
<output>20</output>

<gadget id="calculator">20 - 2.8</gadget>
<output>17.2</output>

<gadget id="calculator">24 + 30 + 17.2</gadget>
<output>71.2</output>

<gadget id="calculator">71.2 * 2.8</gadget>
<output>199.36</output>

<result>199.36</result>