25 x 20,13 + 4 x 20,13 - 2013 x 20,33 + 2013 x 20,04
= 20,13 x ( 25+4) - 2013 x ( 20,33 - 20,04)
= 20,13 x 29 - 2013 x 0,29
= 20,13 x 100 x 0,29 - 2013 x 0,29
= 2013 x 0,29 - 2013 x 0,29
= 0
Ta có:25×20,13+4×20,13-2013×20,33+2013×20,04
=503,25+80,52-40924,29+40340,52
=0
Mk lm chuẩn trên chuẩn đó,k mk nhé!!!