`7,15:0,5+7,15xx9-7,15`
`=7,15xx2+7,15xx9-7,15`
`=7,15xx(2+9-1)`
`=7,15xx10`
`=71,5`
\(7,15:0,5+7,15\times9-7,15\\ =7,15\times2+7,15\times9-7,15\\ =7,15\times\left(2+9-1\right)\\ =7,15\times10\\ =71,5\)
7,15:0,5+7,15×9−7,157,15:0,5+7,15×9-7,15
=7,15×2+7,15×9−7,15=7,15×2+7,15×9-7,15
=7,15×(2+9−1)=7,15×(2+9-1)
=7,15×10=7,15×10
=71,5
#luan nguyen