1. Tim tat ca cac so co 2 chu so sao cho moi so gap 2 lan tich cua no?

2. Tim so nguyen to co 3 chu so biet rang neu viet so do theo thu tu nguoc lai thi ta duc 1 so la lap phuong cua 1 so tu nhien?

3. Tim so tu nhien co 4 chu so biey chu so hang nghin bang chu so hang don vi chu so hang tram bang chu so hang chuc va so do viet duoc duoi dang tich cua 3 so nguyen to lien tiep?

Tim mot so tu nhien co 2 chu so,biet rang neu viet cac chu so cua so ay theo thu tu nguoc lai thi duoc so moi gap so ban dau 3 lan va 13 don vi

tim mot so tu nhien co hai chu so, biet rang neu viet cac chu so cua so ay theo thu tu nguoc lai thi duoc so moi, lay so moi chia cho so ban dau thi duoc thuong la 3 du 13 

tim so tu nhien co hai chu so .Biet rang tong cac chu so bang 6 va neu them vao so don vi thi duoc mot so cung viet bang cac chu so do nhung theo thu tu nguoc lai

Giai bai toan nay ho minh voi tim 1 so co 4 chu so biet rang neu viet cac chu so cua no theo thu tu nguoc lai thi ta duoc mot so bang 4 lan so da cho?

tim 1 so tu nhien co 2 chu so biet rang neu viet cac chu so cua so y theo thu tu nguoc lai thi duoc so moi lay so moi chia cho so ban dau thi duoc thuong la 3 DU 13

Tim so co ba chu so , biet rang neu viet cac chu so theo thu tu nguoc lai thi duoc mot so moi lon hon so ban dau 792 don vi

tim mot so tu nhien  co 5 chu so biet rang so gom 5 chu so tren viet theo thu tu nguoc lai thi bang 4 lan so phai tim vay so do la

tim so tu nhien co 2 chu so biet neu cong no voi so gom 2 chu so ay viet theo thu tu nguoc lai thi duoc so chinh phuong