A full glass of milk is 300ml, and my mother drank half of it and left. Xiaohua filled the glass with boiling water. After my mother came back, she drank half of it and left. Xiaohua filled the glass with boiling water again. This time, after my mother came back, she drank all the milk and water in the glass. Do you know how many milliliters of milk and water your mother drinks?
一满杯牛奶有300毫升，妈妈喝了一半离开了，小华用开水把杯子加满．妈妈回来后又喝了一半离开了，小华又用开水把杯子加满．这次，妈妈回来后把杯里的牛奶和水全部喝完．你知道妈妈喝的牛奶和水一共有多少毫升吗？
<gadget id="calculator">300 / 2</gadget>
<output>150</output>

<gadget id="calculator">150 * 2</gadget>
<output>300</output>

<gadget id="calculator">300 + 300</gadget>
<output>600</output>

<result>600</result>