=34. 15 -34.10 -15 . 34 +15.10
= 15.10 -34.10
=150-340
=-190
34.(15 - 10) - 15.( 34 - 10)
= 34 . 15 - 34 . 10 - 15 . 34 - 15 . 10
= (34 .15 - 34 . 15) - 34 . 10 - 15 . 10
= 0 - 10.( 34 - 15)
= 0 - 10 . 19
= -190
=34.15+15.24=>=15+(34.24)=>=15+816=>=831 .Chúc bạn học tốt!