A=a000+b00+c0+d+542+37+4=abcd+583
B=ab0d+c0+50+507=abcd+557
ta có : abcd+583>abcd+557
=> A>B
A=a000+b00+c0+d+542+37+4=abcd+583
B=ab0d+c0+50+507+abcd+557
ta co :abcd+583>abcd+557
nen A>B
A=a000+542+b00+37+c0+4+d=abcd+583
B=ab0d+50+0c0+507=abcd+557
Vì:A=abcd+583>B=abcd+557
=> A>B
A=a000+b00+co+d+542+37+4=abcd+583
B=ab0d+c0+50+507=abcd+557
ta co abcd+583>abcd+557
=>A>B
A=a000+b00+c0+d+542+37+4=abcd+583
B=ab0d+c0+50+507=abcd+557
ta có : abcd+583>abcd+557
=> A>B