Ban An phai tim tat ca cac so co 3 chu so lon hon 500 ma tong cac chu so cua moi so do deu = 12, dong thoi chu so hang don vi = trung cong cua chu so hang tram va hang chuc. Hoi ban An tim duoc nhieu nhat may so thoa man yeu cau?

tim so co 3 chu so lon nhat co cac chu so khac nhau ma cac chu so hang don vi bang trung binh cong cua chu so hang tram va chu so hang chuc . tim so do

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 

Tim mot so co ba chu so biet trung binh cong cua ba so do bang 2va chu so hang tram bang tong cac chu so hang chuc va hang don vi

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

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 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 BA CHU SO BIET TRUNG BINH CONG 3 SO DO BANG 3 ,CHU SO HANG DON VI GAP DOI TONG CAC CHU SO HANG TRAM VA HANG CHUC

khi doi cho chu so hang chuc va chu so hang don vi cua 1 so cho nhau thi ta duoc 1 so moi nho hon so ban dau 26 don vi.tim so ban dau biet rang trung binh cong cac chu so cua no bang 7 va so do co 3 chu so