Contact us
Choose a category below so we can get back to you as quickly as possible.
是過程吧 設乙為x 5/21x+4/21x+x=310 10/7x=310 x=217 則乙為217元 甲155/3元 丙124/3元
We and our partners use cookies and other technologies to analyze traffic and optimize your experience. View more info and control your cookies settings at any time in our Cookies Policy.