The four numbers 2, 3, 5, and 7 can form many four-digit numbers without repeating numbers. In the four-digit number, there are two numbers that are multiples of 25, and the difference between these two numbers is 450. So, what is the sum of these two four-digit numbers?
由2、3、5、7四个数字能组成许多没有重复数字的四位数．而在组成的四位数中，有两个数是25的倍数，且这两个数的差是450．那么，这两个四位数的和是多少．
<gadget id="calculator">3_725 + 3_275</gadget>
<output>7_000</output>

<result>7_000</result>