Naughty got 84 points in this math test, which is 20% higher than the last test score. What was the last test score?
淘气这次数学测验得了84分，比上次的测验分数提高了20%，上次测验的分数是多少？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">84 / (6/5)</gadget>
<output>70</output>

<result>70</result>