In a glass of water, 101.2 ml is poured out for the first time, and 250.38 ml is poured out for the second time, leaving 98.42 ml. How many ml does this glass of water have?
一杯水，第一次倒出101.2毫升，第二次倒出250.38亳升，还剩下98.42毫升，这杯水原有多少毫升？
<gadget id="calculator">101.2 + 250.38</gadget>
<output>351.58</output>

<gadget id="calculator">98.42 + 351.58</gadget>
<output>450</output>

<result>450</result>