tim so co ba chu so biet rang neu viet them chu so 1 vao ben phai so do thi ta duoc mot so gap 3 lan so co duoc bang cach viet them chu so 2 vao ben trai so do
tim so co 4 chu so, biet rang khi viet them chu so 5vao ben phai so do ta duoc so lon gap 5 lan so nhan duoc khi ta viet them chu so 1 vao ben trai so do
tim mot so co 3 chu so , biet rang khi viet them chu so 3 vao ben trai so do ta duoc mot so gap 5 lan so can tim
Tim mot so tu nhien co 5 chu so , biet rang neu viet them 2 chu so vao ben phai so do thi duoc so lon gap 3 lan so viet them chu so 2 vao ben trai so do .
tim 1 so co 2 chu so biet rang neu viet them vao ben trai ben phai so do 1 chu so 5 ta duoc 1 so moi co 4 chu so gap 75 lan so phai tim
tim so co 3chu so biet rang khi viet them chu so 3 vao ben trai so do ta duoc so moi gap 5 lan so phai tim
TBC 3 so la 12,7 va gap 4 lan ST1.Tim ST2 biet ST3 la 2,19
tong 3 so bang 280 biet ti so+ giua st1 va st2 la 3/4 ti so+ giua st2 va st3 la 6/7 tim st1
cho 3 so co tong la 441 biet 30% ST1 =50% ST2 va =150% ST3 tim ST1