When Zhao Ping was doing the calculation problem, due to her carelessness, she wrote 8 by mistake in the ones place of the subtrahend, and wrote 1 in the 7 in the tens place. The difference obtained in this way is 189. What is the correct difference?
赵萍在做计算题时，由于粗心大意，把被减数个位上的3错写成8，把十位上的7错写成1，这样得到的差是189，正确的差是多少．
<gadget id="calculator">73 - 18</gadget>
<output>55</output>

<gadget id="calculator">189 + 55</gadget>
<output>244</output>

<result>244</result>