A=123.123
=123.(121+2)
=123.121+123.2
B=121.124
=121.(123+1)
=121.123+121.1
vì 123.121 = 121.123
và 123.2 > 121.1
=> 123.123 > 121.124
Vậy A > B.
B=121.124=121.(123+1)=121.123+121.1
A=123.123=123.(121+2)123.121+123.2
Vi 123.2>121.1=>A>B
A= 123.123
= 123. (121+2)
= 123.121+123.2
B= 121.124
= 121.(123+1)
= 121.123+121.1
Vì 123.2 > 121.1 nên A > B