What is the sum of the largest three-digit number and the smallest three-digit number using the three numbers 5, 0, and 7?
用5、0、7这个三个数字组成最大的三位数和最小的三位数的和是多少．
<gadget id="calculator">750 + 507</gadget>
<output>1_257</output>

<result>1_257</result>