goi so do la abc
=> 100a+10b+c = 5.a.b.c
=> c chia het cho 5 =>c=5
20a +2b +1 =5.a.b (<=> (5a- 2)(4-b) +9=0 => b>4)
2b+1 chia het cho 5 => b=2,7(2 loai)
b=7 => a=1
vay so do la 175
Tim so tu nhien co 2 chu so biet rang so do gap doi tich cac chu so cua no
tim so tu nhien co 2 chu so biet rang so do hon 7 lan tong cac chu so cua no la 6 don vi
tim so tu nhien co 3 chu so biet rang neu tang moi chu so cua no len n don vi thi ta duoc mot so co 3 chu so gap n lan so da cho
Ai biet thi giup minh voi nha
Cau hoi la :tim so tu nhien co 5 chu so biet rang neu viet them chu so 2 vao dang sau so do thi duoc so lon gap 3 lan so co duoc bang cach viet them chu so 2 vao dang truoc so do
[ ai lam dung minh se tich cho]
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
tim mot so co 4 chu so biet rang khi viet them chu so 3 vao ben trai so do thi duoc so moi gap 7 lan so phai tim
GIUP EM NHA MOI NGUOI !!
chung to rang
1 số tu nhien mà - đi tổng cua cac chu so cua so do thi chia het cho 9
giúp cái nha
hay viet
tat cac cac so co 2 chu so biet rang chu so hang don vi gap doi chu so hang chuc
mot so le co 3 chu so biet rang so do chia cho 5 du 4 va neu chuyen chu so hang do len dau thi ta duoc 1 so moi bang ba lan so ban dau cong them voi 3 . tim so do
