Aileen scored 70 points in the first math test, and 91 points in the second test. How many percent did she improve?
爱玲第一次数学测试考了70分，第二次考了91分，提高了百分之几？
<gadget id="calculator">91 - 70</gadget>
<output>21</output>

<gadget id="calculator">21 / 70</gadget>
<output>3/10 = around 0.3</output>

<result>3/10 = around 0.3</result>