There is a three-digit number, if you follow the procedure below: ① multiply the hundreds digit by 5; ② subtract 10; ③ multiply by 2; ④ add the tens digit; ⑤ multiply by 10; ⑥ add the ones digit , and finally get a new three-digit number 688, what is the original three-digit number?
有一个三位数，若按以下程序进行操作：①将百位数字乘以5；②减去10；③乘以2；④加上十位数字；⑤乘以10；⑥加上个位数字，最后得到一个新的三位数688，则原三位数是多少．
<result>888</result>