In an oral arithmetic competition, Xiao Ming completed 80 questions in 10 minutes, and got 78 questions correct. What is the correct rate of his calculations?
一次口算比赛，小明10分钟完成80道题，正确的有78道，他计算的正确率是多少．
<gadget id="calculator">78 / 80</gadget>
<output>39/40 = around 0.975</output>

<gadget id="calculator">100 / 100</gadget>
<output>1</output>

<gadget id="calculator">(39/40) * 1</gadget>
<output>39/40 = around 0.975</output>

<result>39/40 = around 0.975</result>