1= 2-1=200-199=5-4=1-0=10000-9999
#)Trả lời :
1 = 2 - 1
1 = 1 + 0
1 = 4 - 3
1 = 5 - 4
1 = 9 - 8
#~Will~be~Pens~#
1 = 0 + 1
1 = 2 - 1
1 = 3 - 2
1 = 4 - 3
1 = 5 - 4
1 = 9 - 8
1 = 8 - 7
1 = 7 - 6
1 = 6 - 5
1 = 5 - 4
1 = 0 + 1
1 = 2 - 1
1 = 3 - 2
1 = 4 - 3
1 = 5 - 4