1253.75-1755: 5):20012002
= [(53)3.75-1755:5):20012002
= (59.75-1755:5):20012002
= (55.54.74.7-1754.175:5):20012002
= (55.354.7-1754.35):20012002
= (5.7.354.54-1754.35):20012002
= (35.1754-1754.35):20012002
= 0:20012002
= 0
toan copy ket qua cua ban dau tien