Flour is 0.80 yuan more expensive than rice per kilogram. If a customer buys 40kg of rice, there is still a shortfall of 4.00 yuan. If he does not buy rice and buys 30kg of flour, he still has a shortfall of 2.00 yuan. Calculate how much this customer brought?
面粉每千克比大米贵0.80元，一顾客若买40kg大米，还缺4.00元，若不买大米，而买30kg面粉，则还缺2.00元，算一算这位顾客带了多少钱？
<gadget id="calculator">0.8 * 30</gadget>
<output>24</output>

<gadget id="calculator">24 - 4</gadget>
<output>20</output>

<gadget id="calculator">2 + 20</gadget>
<output>22</output>

<gadget id="calculator">40 - 30</gadget>
<output>10</output>

<gadget id="calculator">22 / 10</gadget>
<output>11/5 = around 2.2</output>

<gadget id="calculator">(11/5) * 40</gadget>
<output>88</output>

<gadget id="calculator">88 - 4</gadget>
<output>84</output>

<result>84</result>