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)
tong cac chu so cua 1 so co 3 chu so la 21 chu so hang don vi lon hon chu so hang chuc .neu ta doi vi tri chu so hang don vi va chu so hang tram thi duoc mot so moi co gia tri lon hon so cu la 198. tim so cu .
giup mk nhe
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 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 chu so hang tram
Gọi số đó là abc (a>0;a,b,c<10)
Ta có:
a=2c và a=b \(\Rightarrow\)b=2c
a+b+c=20
2c+2c+c=20
5c=20
c=4
=>a=8
Vậy abc=884
Ta co so do :
chu so hang tram [---------]-----------]
chu so hang chuc [----------]-----------] [ 20 ]
chu so hang don vi [----------]
chu so hang don vi la
20 : [2 + 2 +1 ]= 4
chu so hang tram va chuc la
4 x 2 = 8
so phai tim 884
Tim so tu nhien co 2 chu so biet rang chu so hang chuc lon hon chu so hang don vi la 2 va so do lon hon tong cac binh phuong cac chu so cua no la 1.
tim so tu nhien co 4 chu so khac nhau lon hon 3142 ma co tong cac chu so bang 6 va chu so hang chuc be hon chu so hang don vi
Viet tap hop cac so tu nhien co hai chu so,trong do:
a) Chu so hang chuc nho hon chu so hang don vi la 5
b) Chu so hang chuc gap 4 lan chu so hang don vi
c) Chu so hang chuc nho hon chu so hang don vi, tong hai chu so bang 14
A = { 16; 27; 38; 49 }
B = { 41; 82 }
C = { 59; 68 }
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
126 va 216 nha ban
tim so tu nhien co 4 chu so biet rang so nay chia 3 du 2, cac chu so hang ngan,hang chuc, hang tram, hang don vi lan luot la la cac so tu nhien lien tiep tang dan va trong 4 chu so do khong co chu so nao bang 7