Use 2 kilograms of toffee at 8.4 yuan per kilogram, 3 kilograms of fruit candy at 5.6 yuan per kilogram, and 4 kilograms of halva at 6.9 yuan per kilogram, and mix them into assorted candies. How much is the price per kilogram of this assorted sugar?
用每千克8.4元的奶糖2千克，每千克5.6元的水果糖3千克，每千克6.9元的酥糖4千克，混合成什锦糖．这种什锦糖每千克的价格是多少元？
<gadget id="calculator">8.4 * 2</gadget>
<output>16.8</output>

<gadget id="calculator">5.6 * 3</gadget>
<output>16.8</output>

<gadget id="calculator">6.9 * 4</gadget>
<output>27.6</output>

<gadget id="calculator">16.8 + 16.8 + 27.6</gadget>
<output>61.2</output>

<gadget id="calculator">2 + 3 + 4</gadget>
<output>9</output>

<gadget id="calculator">61.2 / 9</gadget>
<output>6.8</output>

<result>6.8</result>