tim so tu nhien co 2 chu so ,biet rang neu viet them chu so 0 xen giua chu so hang chuc va hang don vi cua so do ta duoc so moi gap 10 lan so can tim .Neu viet them chu so 1 vao ben trai so vua nhan duoc thi so do gap len 3 lan.

tim so tu nhien co 2 chu so biet rang neu viet chu so 0 xen giua chu so hang chuc va hang don vi cua so do ta duoc so moi gap 10 lan so can tim . Neu viet them chu so 1 vao ben trai so vua nhan duoc thi so do gap len 3 lan . So can tim la

tim mot so co 2 chu so biet rang khi viet them chu so 0 vao giua 2 chu so do thi duoc 1 so co 3 chu so gap 9 lan so ban dau

tim 1 so co 2 chu so biet rang neu them vao chu so 0 vao giua hai chu so do thi duoc 1 so co 3 chu so gap 9 lan so ban dau

so do la

1.Cho so N la so co hai chu so chia het cho 3.Neu viet xen so 0 vao giua hai chu so do roi cong no voi hai lan chu so hang chuc cua so N ta duoc so moi gap 9 lan so N.Tim so do

2.Tong hai so thap phan la 60,1.Neu dich dau phay cua so nho sang ben phai mot hang roi dem tru di so lon thi ta duoc 219,52.Tim hai so do.

3.Tim so co hai chu so biet neu ta them so 33 vao giua hai chu so do thi duoc mot so moi gap so phai tim 89 lan.

tim so co 2 chu so biet rang neu them chu so 0 xen giua chu so hang chuc va hang don vi cua so ta duoc  lon gap 10 lan so da cho neu them chu so 1 vao ben trai so vua nhan duoc thi so do tang lon hon 3 lan

tim mot so tu nhien co 2 chu so biet rang neu viet them chu so 0 xen vao giua hang chuc va hang don vi cua so da cho,neu viet them chu so 1 vao ben trai so vua nhan duoc thi so do lai tang len 3 lan

tim 1 so co 2 chu so biet rang them chu so 0 vao giua 2 chu so thi so do duoc mt so co 3 chu so gap 9 lan so ban dau

tim so co 2 chu so, biet rang neu ta viet them chu so 1 vao giua 2 so cua so do ta duoc so moi gap so can tim 9 lan. tinh so ban dau