tim  so co 3 chu so co tong cac chu so la 20 va ti so giua chu so hang tram voi chu so hang don vi la 2, con chu so hang chuc bang voi chu so hang tram.

giai ro rang nhe

Tim 1 so co 3 chu so biết chu so hang chuc bang tong chu so hang tram voi chu so hang don vi. Chia chu so hang   tram cho chu so hang dọn vi ta được thương la 3 va du 1. Tich cua so tan cung voi 7 la mot so co chu so tan cung ben phai la 4

Tong cac chu so cua so tu nhien co 3 chu so la 12. Chu so hang chuc bang tong chu so hang tram va hang don vi. Neu doi vi tri chu so hang tram va hang don vi thi duoc so moi hon so cu la 396. Tim so ban dau.

                       (giải ra)

tim tat cac so tu nhien co ba chu so thoan man cac tinh chat sau : co tong cac chu so bang 9 chu so hang chuc lom hon chu so hang don vi la 2 don vi va neu ta doi chu so hang tram cho hang don vi thi duoc so moi lon hon so ban dau la 198 don vi

tim so co 3 chu so. Biet trung binh cong cua 3 chu so la 2 va chu so hang tram bang tong chu so hang chuc va hang don vi. Tim 3 chu so do ?

Tim so co 3 chu so biet chu so hang tram bang hieu giua chu so hang chuc voi chu so hang don vi . ta duoc thuong la 2 va du 2 

giup minh voi minh sap di hoc roi 

Tim mot so co ba chu so biet hieu giua chu so hang

tram va chu so hang don vi la so lon nhat co ba chu so,

 chu so hang chuc kem chu so hang tram la 4.

tim so co 3 chu so biet chu so hang tram nho hon chu so hang chuc,chu so hang chuc nho hon chu so hang don vi va tong cac chu so do bang 6

tim so co chu so biet trung binh cong cua 3 chu so bang 2 va chu so hang tram bang tong cac chu so hang chuc va hang don vi