a=(-2/3+1 1/4-1/6).-24/10 b=13/15.0,25.3+(8/15-1 19/60):1 23/24 30/06/2021 Bởi Reese a=(-2/3+1 1/4-1/6).-24/10 b=13/15.0,25.3+(8/15-1 19/60):1 23/24
`a = (-2/3 + 1 1/4 – 1/6) . \frac{-24}{10}` `= (-2/3 + 5/4 – 1/6) . \frac{-12}{5}` `= 5/12 . \frac{-12}{5}` `= -1` ==================================== `b= 13/15 . 0,25 . 3 + ( 8/15 – 1 19/60) : 1 23/24` `= 13/15 . 1/4 . 3 + ( 8/15 – 79/60) : 47/24` `= 13/60 . 3 + (-47/60) : 47/24` `= 13/20 + (-2/5)` `= 1/4` Bình luận
Đáp án + Giải thích các bước giải: `a)` `A=(-2/3+1 1/4-1/6).(-24)/10` `=(-2/3+5/4-1/6).(-12)/5` `=(-2)/3 . (-12)/5+5/4 . (-12)/5 – 1/6 . (-12)/5` `= 8/5+(-3)+2/5` `= 2+(-3)=-1` `b)` `13/15 . 0,25 . 3 + ( 8/15 – 1 19/60 ) : 1 23/24` `= 13/15 . 1/4 . 3 + ( 8/15 – 79/60 ) : 47/24` `= 13/20 + (-47)/60 . 24/47` `= 13/20 – 2/5 = 13/20 – 8/20 = (13-8)/20 = 5/20=1/4` Bình luận
`a = (-2/3 + 1 1/4 – 1/6) . \frac{-24}{10}`
`= (-2/3 + 5/4 – 1/6) . \frac{-12}{5}`
`= 5/12 . \frac{-12}{5}`
`= -1`
====================================
`b= 13/15 . 0,25 . 3 + ( 8/15 – 1 19/60) : 1 23/24`
`= 13/15 . 1/4 . 3 + ( 8/15 – 79/60) : 47/24`
`= 13/60 . 3 + (-47/60) : 47/24`
`= 13/20 + (-2/5)`
`= 1/4`
Đáp án + Giải thích các bước giải:
`a)`
`A=(-2/3+1 1/4-1/6).(-24)/10`
`=(-2/3+5/4-1/6).(-12)/5`
`=(-2)/3 . (-12)/5+5/4 . (-12)/5 – 1/6 . (-12)/5`
`= 8/5+(-3)+2/5`
`= 2+(-3)=-1`
`b)`
`13/15 . 0,25 . 3 + ( 8/15 – 1 19/60 ) : 1 23/24`
`= 13/15 . 1/4 . 3 + ( 8/15 – 79/60 ) : 47/24`
`= 13/20 + (-47)/60 . 24/47`
`= 13/20 – 2/5 = 13/20 – 8/20 = (13-8)/20 = 5/20=1/4`