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

- tim so chu so chan co 4 chu so 

- viet tat ca cac so tu 100 den 999phai dung bao nhieu chuvso 9

-co bao nhieu so le co 3 chu so

- viet 1000 sdo tu nyhien dau tien hoi chu so 3 cco mat bao nhieu lan

-viet tap hop cac so tu nhien co 2 chu so trong do a ) chu so hang chuc nho hon hang don vi la 4 b) chu so hang chuc gap 3 lan chu so hang don vi   c) chu so hang chuc nho hon chu so hang don vi ( tong 2 chu so = 12) 

viet tap hop cua cac so tu nhien co 2 chu so trong do

a chu so hang chuc nho hon chu so hang don vi la 5

b chu so hang chuc gap bon lan chu so hang don vi

c chu so hang chuc nho hon chu so hang don vi tong hai so do bang 14

ai giup mk thi se kb nha

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 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.

cho B la tap hop cac so co 2 chu so, trong do chu so hang chuc nho hon chu so hang don vi la 5. tap hop B co so phan tu?

tap hop a cac so tu nhien co 2 chu so trong do chu so hang chuc lon hon chu sio hang don vi la 2

viet tap hop cac so tu nhien co hai chu so,trong do:

a,chu so hang don vi lon hon chu so hang chuc 4 don vi

b,chu so hang don vi gap 3 lan chu so hang chuc

c,chu so hang don vi nho hon chu so hang chuc va tong hai chu so =17

viet tat ca cac so co hai chu co tong cua chu so hang chuc va chu so hang don vi la 8