1.tim so bi chia trong phep chia cho 12 co thuong la 35 va so du la so le co 2chu so

2.hieu cua so lon nhat co 4 chu so khac nhau va so nho nhat co 4 chu sola bao nhieu

3.mot hinh chu nhat co chieu dai gap ruoi chieu rong. Neu moi chieu tang them 1m thi duoc hinh chu nhat moi co dien tich tang them 26m2. Tinh chu vi hinh chu nhat

4.trung binh cong cua 2 phan so bang 5/12. Phan so thu nhat hon phan so thu hai 1/6. Tim phan so thu nhat

5.tim y biet (5/7 - y) nhan 4/5 =7/10 + 1/2

6.hieu 2 so =1/3 so be.Tong 2 so la 63. Tim so be

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?