Ta có :
18ab : ab = 25
1800 + ab = 25 x ab
1800 = 24 x ab
1800 : 24 = ab
75 = ab
75 nha thi violympic rồi đúng 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000%