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 mot so tu nhien co 2 chu so biet neu viet them chu so 0 vao giua chu so hang chuc va hang don vi thi ta duoc so tu nhien gap 9 lan so cu
tim so co hai chu so biet rang neu ta viet them chu so 1 vao giua hai chu so cua so do ta duoc so moi gap so 9 lan so phai tim.tim so phai tim
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 1so co 2 chu so biet so do chia het cho 9 . neu viet them chu so 0 vao giua 2 chu so cua so do roi lay so moi tru di 6 lan chu so hang tram ta duoc so bang 8 lan so da cho
tim tat ca cac so tu nhien khac 0 sao cho khi viet them chu so 0 vao giua chu so hang chuc va chu so hang don vi thi so do duoc gap len 9 lan
Tim mot do tu nhien co 3 chu so abc biet rang neu doi chu so hang tram va chu so hang don vi cho nhau thi so moi lon hon so cu 792 đơn vị ,chu so hang don vi gap 3 lan chu so hang chuc
tim so tu nhien co 3 chu so biet rang neu viet them chu so 1 vao truoc so do thi dc so moi gap 9 lan so ban dau
Bai 1:Cho so tu nhien A co 4 chu so. Co chu so hang don vi gap 3 lan chu so hang tram chu so hang chuc gap 8 lan chu so hang nghin. Biet A chia het cho 9.Tim A
Bai 2: Tim tat ca cac so dang 6x14y. Biet rang so do chia het cho 3,4 va 5