vua doc xong biet lien thoi.. 1 to 9000 x 3 = 27... nhu vay phai cong 3000 da bot cho khach.. ....tai sao phai cong 2000 cua anh nhan vien da lay bot bo tui ?. trick trick trick...


27+3 =30.....
moi nguoi khach nhan lai 1000 x3 = 3000 +27 = 30000