sai roi phai lam the nay
11 cai banh chia cho 12 nguoi tuc moi nguoi duoc 11 : 12 = 11/12 ( cai banh )
cach chia banh nhu sau :
-Chia 2 cai banh ma moi cai chia thanh 6 phan bang nhau => khi do moi nguoi 1/6 cai banh.
-Chia 3 cai banh ma moi cai chia thanh 4 phan bang nhau => khi do moi nguoi 1/4 cai banh.
-Chia 6 cai banh ma moi cai chia thanh 2 phan bang nhau => khi do moi nguoi 1/2 cai banh.
=> Moi nguoi lay : 1/6 + 1/4 + 1/2 = 2/12 + 3/12 + 6/12 = 11/12.