The school needs to spend a sum of money to buy a batch of desks and chairs. If you buy a set of 500 yuan each, there will be 800 yuan left; if you buy a set of 600 yuan each, you will need to buy two sets less than planned. How much does the school pay for tables and chairs?
学校要用一笔钱添置一批桌椅，如果买每套500元的，则还剩800元；如果买每套600元的，则要比计划买的少两套．学校买桌椅的钱有多少元？
<gadget id="calculator">1_200 + 800</gadget>
<output>2_000</output>

<gadget id="calculator">600 - 500</gadget>
<output>100</output>

<gadget id="calculator">2_000 / 100</gadget>
<output>20</output>

<gadget id="calculator">20 * 500</gadget>
<output>10_000</output>

<gadget id="calculator">10_000 + 800</gadget>
<output>10_800</output>

<result>10_800</result>