Solve the problem by formulating the equation: At the beginning of the school year, the experimental primary school purchased 200 sets of desks and chairs. It cost a total of 21,960 yuan, 69.9 yuan per table, how much is each chair?
列方程解决问题：开学初，实验小学新购进200套课桌椅，一共花了21960元，每张桌子69.9元，每张椅子多少元？
<gadget id="calculator">21_960 / 200</gadget>
<output>549/5 = around 109.8</output>

<gadget id="calculator">(549/5) - 69.9</gadget>
<output>39.9</output>

<result>39.9</result>