441+304=?,247+478=?,480+717=?
728-15=?,910-696=?,910-107=?
40+?=834,212+?=748,380+?=960
89*7=?,78*9=?,487*4=?
576/8=?,715/5=?,744/6=?
---
?-206=830-421,105+193+426+157=?
786-238=?+364,500+331+250-957=?
259+?+346=907,484+466-272-321=?
225+?-556=497,999-283-150-435=?
爬栏杆危险