Mom and Aunt Li went shopping in the supermarket together. Mom bought 5 kg of rice and 4 kg of flour and paid a total of 29.2 yuan. Aunt Li also bought the same 4 kg of rice and 5 kg of flour and paid a total of 28.4 yuan. How much is a kilogram of rice?
妈妈和李阿姨一起到超市购物，妈妈买了5千克大米和4千克面粉共付29.2元，李阿姨也买了同样的4千克大米和5千克面粉则共付28.4元，每千克大米多少钱？
<gadget id="calculator">29.2 - 28.4</gadget>
<output>0.8</output>

<gadget id="calculator">0.8 * 4</gadget>
<output>3.2</output>

<gadget id="calculator">3.2 + 29.2</gadget>
<output>32.4</output>

<gadget id="calculator">5 + 4</gadget>
<output>9</output>

<gadget id="calculator">32.4 / 9</gadget>
<output>3.6</output>

<result>3.6</result>