Xiao Ming did a subtraction problem and wrote the subtrahend 72 as 27 by mistake, and the difference he got at this time was 309. What is the correct difference.
小明做一道减法题，把减数72错写成27，这时得到的差是309．正确的差是多少．
<gadget id="calculator">72 - 27</gadget>
<output>45</output>

<gadget id="calculator">309 - 45</gadget>
<output>264</output>

<result>264</result>