When Xiaoli did the subtraction calculation, she wrote "6" for the "3" in the subtracted tens digit, and the result was 254. What is the correct answer?
小丽做减法计算时，把被减数十位上的"3"写成"6"，结果是254，正确的答案是多少．
<gadget id="calculator">254 - 30</gadget>
<output>224</output>

<result>224</result>