Xiaohong walks 20 meters per minute when she goes to school from home, and walks 30 meters per minute along the same road after school. How many meters does Xiaohong walk on average per minute when going to school and after school?
小红从家上学时每分钟行20米，放学沿原路回家每分钟行30米．小红上学和放学平均每分钟行多少米．
<gadget id="calculator">1 + 1</gadget>
<output>2</output>

<gadget id="calculator">1 / 20</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">1 / 30</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">(1/20) + (1/30)</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">2 / (1/12)</gadget>
<output>24</output>

<result>24</result>