999.135
=135.(1000-1)
=135.1000-135.1
=135000-135
=134865
b) 998.121
=(1000-2).121
=1000.121-2.121
=121000-242
=120758
999.135
=135.(1000-1)
=135.1000-135.1
=135000-135
=134865
b) 998.121
=(1000-2).121
=1000.121-2.121
=121000-242
=120758
999.135
=135.(1000-1)
=135.1000-135.1
=135000-135
=134865
b) 998.121
=(1000-2).121
=1000.121-2.121
=121000-242
=120758
999.135
=135.(1000-1)
=135.1000-135.1
=135000-135
=134865
b) 998.121
=(1000-2).121
=1000.121-2.121
=121000-242
=120758
999.135
=(999+1).(135-1)
=1000.134
=134000
998.121
=(998+2).(121-2)
=1000.119
=119000
tính nhẩm
999.135 998.121
Giúp mk với cảm ơn trước !
Toán lớp 6
999.135
=135.(1000-1)
=135.1000-135.1
=135000-135
=134865
b) 998.121
=(1000-2).121
=1000.121-2.121
=121000-242
=120758
999 . 135 = (1000 - 1 ) . 135 = 135000 - 135 = 134865
998.121 = (1000 - 2 ) .121 = 121000- 242 = 120758
