`a) 45 xx 15 + 56 xx 15 - 15`
`= 45 xx 15 + 56 xx 15 - 15 xx 1`
`= 15 xx ( 45 + 56 - 1)`
`= 15 xx 100`
`= 1500`
__
`b)561xx97-7xx561+561xx10`
`=561xx(97-7+10)`
`=561xx100`
`=56100`
Đúng 1
Bình luận (0)
45×15+56×15−15a)45×15+56×15-15
=45×15+56×15−15×1=45×15+56×15-15×1
=15×(45+56−1)=15×(45+56-1)
=15×100=15×100
=1500=1500
__
b)561×97−7×561+561×10b)561×97-7×561+561×10
=561×(97−7+10)=561×(97-7+10)
=561×100=561×100
=56100
Đúng 1
Bình luận (0)
