1 .trung binh cong cua hai phan so la 5/12 .neu tang phan so thu nhat gap 2 lan thi trung binh cong cua chung bang 2/3 .tim hai phan so do .
2.trung binh cong cua ba phan so la 13 /36 .neu tang phan so thu nhat gap 2 lan thi trung binh cong cua chung bang 19/36 ,cho biet phan so thu hai lon hon phan so thu ba 1 /12. tim ba phan so do .
tong cua hai so thap phan bang 8,4.Tim hai so do, biet neu so thu nhat tang 4 lan va giu nguyen so thu hai thi tong moi la
tim hai so biet 40% so thu nhat bang 1/4 so thu hai. tong hai so la 13/23
tim hai so biet 40 o\o so thu nhat bang 1\4 so thu hai tong hai sso la 13\23
Tim hai so thap phan co tong la 14,17 . Biet 1/3 so thu nhat bang 2/7 so thu hai.
tong hai so la 96 tim hai so biet so thu nhat bang 50 phan tram so thu hai
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?
Cho ba so tong cua so thu nhat va so thu hai la 11 phan 20 tong cua so thu hai va so thu ba la 3 phan 4 tong cua so thu nhat va so thu ba la 7 phan 10 Tim ba so do
