There is a three-digit number: the digit on the tens digit is 0, and the sum of the digits on the other two digits is 12. If the ones digit is subtracted by 2 and the hundreds digit is added by 1, the new three-digit number is 100 less than the three-digit number obtained by exchanging the hundreds digit and the ones digit of the original three-digit number, what is the original three-digit number?
有一个三位数：十位上的数字是0，其余两位上的数字之和是12．如果个位数字减2，百位数字加1，所得的新三位数比原三位数的百位数字与个位数字调换所得的三位数小100，则原三位数是多少．
<result>507</result>