Xiaohu used the protractor to measure an angle according to the correct method, but in the end he mistakenly read the inner scale of this angle as the outer scale of 120 degrees. What is the correct degree of this angle?
小虎用量角器按照正确的方法摆放测量一个角，可是最后他错误的把这个角应读的内圈刻度读成了外圈刻度120度，这个角正确的度数应是多少度．
<gadget id="calculator">180 - 120</gadget>
<output>60</output>

<result>60</result>