Xiaodong's home is 800 meters away from the school, and he walks 50 meters per minute. Once, he went to school from home, and after walking 300 meters, he went home again because of something, and then went to school again. How many minutes did Xiaodong walk in total?
小东的家离学校800米，他每分钟走50米．有一次，他从家去学校，走了300米后，因有事又回家，然后再去学校．小东一共走了多少分钟？
<gadget id="calculator">300 * 2</gadget>
<output>600</output>

<gadget id="calculator">800 + 600</gadget>
<output>1_400</output>

<gadget id="calculator">1_400 / 50</gadget>
<output>28</output>

<result>28</result>