For a three-digit number, the hundreds digit is 5 greater than the tens digit, and the ones digit is three times the tens digit; and the sum of the digits of the three digits is 15. What is the three-digit number.
一个三位数，它的百位数比十位数大5，个位数是十位数的3倍；而且这个三位数的各个数位上的数字和是15．这个三位数是多少．
<result>726</result>