Bài 4:
a)x+`3/8`=`16/15`
x =`16/15`-`3/8`
x =`128/120`-`45/120`
x =`83/120`
b)`21/32`-x=`3/8`
x=`21/32`-`3/8`
x=`21/32`-`12/32`
x=`9/32`
c)y : `4/5`=`25/4`x`4/5`
y : `4/5`=5
y =5x`4/5`
y =4
d)`22/5` : y=`11/15`x`5/2`
`22/5` : y=`11/6`
y=`22/5` : `11/6`
y=`12/5`
e)`6/5`-x :`1/2`=`1/2`
x :`1/2`=`6/5`-`1/2`
x :`1/2`=`12/10`-`5/10`
x :`1/2`=`7/10`
x =`7/10`x`1/2`
x =`7/20`
g)`3/5`+`2/7`: x=1
`2/7`: x=1-`3/5`
`2/7`: x=`5/5`-`3/5`
`2/7`: x=`2/5`
x=`2/7` : `2/5`
x=`5/7`
Bài 5:
a)(`1/2`+`1/3`+`1/4`)x X=1+`2/3`+`1/2`
(`6/12`+`4/12`+`3/12`)x X=`6/6`+`4/6`+`3/6`
`13/12`x X=`13/6`
X=`13/6`:`13/12`
X=2
b)(`4/7`+`2/3):(X+`1/2`)=`8/7`+`4/3`
(`12/21`+`14/21`):(X+`1/2`)=`24/21`+`28/21`
`26/21`:(X+`1/2)= `52/21`
X+`1/2`=`26/21`:`52/21`
X+`1/2`=`1/2`
X =`1/2`-`1/2`
X =0
Chúc chủ tus học tốt! Cho mình xin ctlhn ak!
