Question

[Nguyễn Quang Long]

Ti​m 1 so .biet neu them chu so 0 vao ben phai so do va them so1 vao ben trai thi dc so moi gap 50 lan so da cho

Answer 1

[Song phai noi phet]

goi so can tim la ab ( a > 0 ; a , b < 10 )

khi do so moi la : 1ab0

ta co : ab x 50 = 1ab0

      ab x 50 = 1000 + ab x 10

   ab x ( 50 -10 ) = 1000

   ab x 40 = 1000

   ab = 1000 : 40

 ab = 25 . Vay ab = 25

               dap so : 25 dung chuan luon day hoang oi