tim 2 so tu nhien biet rang gap ca hai so do len 3 lan thi duoc 2 so co tong moi = 432 va co ti so la 1/1 tim 2 so
tim 2 so thap phan co tong la 84,99 , biet neu moi so do gap len 100 lan thi khi do 2 so la so tu nhien va co hieu la 749
tim so tu nhien co 2 chu so biet rang neu viet chu so 0 xen giua chu so hang chuc va hang don vi cua so do ta duoc so moi gap 10 lan so can tim . Neu viet them chu so 1 vao ben trai so vua nhan duoc thi so do gap len 3 lan . So can tim la
hai so co tong bang 160 neu gap so thu nhat len 3 lan va gap so thu hai len 5 lan roi cong lai thi duoc tong moi la 678 tim 2 so
1. Tim trung binh cong cua tat ca cac so tu nhien co 4 chu so khac nhau duoc viet boi bon chu so 0;3;5;7.Trung binh cong cua tat ca cac so do la?
2 .Tong cua 3 so bang 5,2. So thu nhat bang 2/3 so thu ba va so thu hai bang 50% so thu ba. Tim so thu hai?
3. Tim mot phan so co mau so bang 25 , biet rang neu cong tu so voi 34 va nhan mau so voi 3 thi duoc phan so moi bang phan so da cho. Tim phan so do?
4. Tim mot phan so biet rang neu cong them 4 vao tu so va giu nguyen mau so thi ta duoc phan so moi bang 1, con neu giu nguyen tu so va cong them 3 thi ta duoc phan so moi bang 1/2 .Tim phan so do?
5. Hay cho biet co tat ca bao nhieu so co 3 chu so ma tong co chu so cua moi so bang 4 . co tat ca bao nhieu so thoa man?
tim 2 so co tong bang 140,biet rang neu gap so hang thu nhat len 5 lan va gap so hang thu hai len 3 lan thi tong moi la 508
tim hai so co tong bang 140 biet rang neu gap so hang thu nhat len 5 lan va gap so hang thu 2 len 3 lan thi tong moi la 508
tim mot so tu nhien co 3 chu so biet rang neu chuyen chu so 7 tan cung cua so do len dau thi duoc mot so moi gap 2 lan so cu va them 21 don vi
tim hai so co tong bang 140 , biet rang neu gap so hang thu nhat len 5 lan va gap so hang thu hai len 3 lan thi tong moi la 508